\u5c06\u5b57\u7b26\u4e32\u6216\u6570\u5b57\u8f6c\u6362\u4e3a\u6574\u6570\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nint('123') # 123
\nint(3.14) # 3<\/p>\n
# \u6307\u5b9a\u8fdb\u5236\u8f6c\u6362
\nint('1010', 2) # 10 (\u4e8c\u8fdb\u5236\u8f6c\u5341\u8fdb\u5236)
\nint('FF', 16) # 255 (\u5341\u516d\u8fdb\u5236\u8f6c\u5341\u8fdb\u5236)<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nint('') # ValueError: invalid literal for int() with base 10: ''
\nint(None) # TypeError: int() argument must be a string, a bytes-like object or a number, not 'NoneType'
\nint('3.14') # ValueError: invalid literal for int() with base 10: '3.14'
\nint(float('inf')) # OverflowError: cannot convert float infinity to integer<\/p>\n
\u5c06\u6570\u636e\u8f6c\u6362\u4e3a\u6d6e\u70b9\u6570\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nfloat('3.14') # 3.14
\nfloat(3) # 3.0<\/p>\n
# \u7279\u6b8a\u503c\u8f6c\u6362
\nfloat('inf') # inf
\nfloat('-inf') # -inf
\nfloat('nan') # nan<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nfloat('') # ValueError: could not convert string to float: ''
\nfloat(None) # TypeError: float() argument must be a string or a number, not 'NoneType'
\nfloat('3.14a') # ValueError: could not convert string to float: '3.14a'<\/p>\n
\u5c06\u5bf9\u8c61\u8f6c\u6362\u4e3a\u5b57\u7b26\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nstr(123) # '123'
\nstr(3.14) # '3.14'
\nstr(True) # 'True'<\/p>\n
# \u7279\u6b8a\u5bf9\u8c61\u8f6c\u6362
\nstr(None) # 'None'
\nstr([1,2,3]) # '[1, 2, 3]'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nstr(float('inf')) # 'inf'
\nstr(float('nan')) # 'nan'
\nstr(object()) # '<object object at 0x…>'<\/p>\n
\u5c06\u503c\u8f6c\u6362\u4e3a\u5e03\u5c14\u7c7b\u578b\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nbool(1) # True
\nbool(0) # False
\nbool('') # False
\nbool('abc') # True<\/p>\n
# \u7279\u6b8a\u503c\u8f6c\u6362
\nbool(None) # False
\nbool([]) # False
\nbool([0]) # True<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nbool(float('inf')) # True
\nbool(float('nan')) # True<\/p>\n
\u521b\u5efa\u5217\u8868\u6216\u5c06\u53ef\u8fed\u4ee3\u5bf9\u8c61\u8f6c\u6362\u4e3a\u5217\u8868\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlist('abc') # ['a', 'b', 'c']
\nlist((1,2,3)) # [1, 2, 3]<\/p>\n
# \u7a7a\u5217\u8868\u521b\u5efa
\nlist() # []<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlist(None) # TypeError: 'NoneType' object is not iterable
\nlist(123) # TypeError: 'int' object is not iterable
\nlist({'a':1}) # ['a'] (\u5b57\u5178\u9ed8\u8ba4\u8fed\u4ee3\u952e)<\/p>\n
\u521b\u5efa\u5143\u7ec4\u6216\u5c06\u53ef\u8fed\u4ee3\u5bf9\u8c61\u8f6c\u4e3a\u5143\u7ec4\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\ntuple([1,2,3]) # (1, 2, 3)
\ntuple('abc') # ('a', 'b', 'c')<\/p>\n
# \u7a7a\u5143\u7ec4\u521b\u5efa
\ntuple() # ()<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\ntuple(None) # TypeError: 'NoneType' object is not iterable
\ntuple(123) # TypeError: 'int' object is not iterable<\/p>\n
\u521b\u5efa\u96c6\u5408\u6216\u53bb\u9664\u53ef\u8fed\u4ee3\u5bf9\u8c61\u4e2d\u7684\u91cd\u590d\u5143\u7d20\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nset([1,2,2,3]) # {1, 2, 3}
\nset('aabbcc') # {'a', 'b', 'c'}<\/p>\n
# \u7a7a\u96c6\u5408\u521b\u5efa
\nset() # set()<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nset(None) # TypeError: 'NoneType' object is not iterable
\nset(123) # TypeError: 'int' object is not iterable
\nset([[]]) # TypeError: unhashable type: 'list'<\/p>\n
\u521b\u5efa\u5b57\u5178\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\ndict(a=1, b=2) # {'a': 1, 'b': 2}
\ndict([('a',1),('b',2)]) # {'a': 1, 'b': 2}<\/p>\n
# \u7a7a\u5b57\u5178\u521b\u5efa
\ndict() # {}<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\ndict(None) # TypeError: cannot convert dictionary update sequence element #0 to a sequence
\ndict(123) # TypeError: cannot convert dictionary update sequence element #0 to a sequence
\ndict([('a',1), None]) # TypeError: cannot convert dictionary update sequence element #1 to a sequence<\/p>\n
\u4ece\u63a7\u5236\u53f0\u8bfb\u53d6\u7528\u6237\u8f93\u5165\u7684\u5b57\u7b26\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# name = input("\u8bf7\u8f93\u5165\u4f60\u7684\u540d\u5b57: ") # \u7528\u6237\u8f93\u5165\u4f1a\u4f5c\u4e3a\u5b57\u7b26\u4e32\u8fd4\u56de<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u8f93\u5165Ctrl+D (Unix) \u6216 Ctrl+Z (Windows) \u4f1a\u5f15\u53d1 EOFError<\/p>\n
\u5c06\u6307\u5b9a\u7684\u5bf9\u8c61\u8f93\u51fa\u5230\u63a7\u5236\u53f0\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nprint('Hello', 'World') # Hello World
\nprint(1, 2, 3, sep='-') # 1-2-3<\/p>\n
# \u53c2\u6570\u8bf4\u660e
\n# sep: \u5206\u9694\u7b26，\u9ed8\u8ba4\u4e3a\u7a7a\u683c
\n# end: \u7ed3\u675f\u5b57\u7b26，\u9ed8\u8ba4\u4e3a\u6362\u884c\u7b26
\n# file: \u8f93\u51fa\u6587\u4ef6\u5bf9\u8c61，\u9ed8\u8ba4\u4e3asys.stdout
\n# flush: \u662f\u5426\u7acb\u5373\u5237\u65b0\u7f13\u51b2\u533a，\u9ed8\u8ba4\u4e3aFalse<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nprint(None) # None
\nprint(float('inf')) # inf
\nprint(float('nan')) # nan<\/p>\n
\u8fd4\u56de\u4e00\u4e2a\u6570\u7684\u7edd\u5bf9\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nabs(-5) # 5
\nabs(3.14) # 3.14<\/p>\n
# \u590d\u6570\u7edd\u5bf9\u503c
\nabs(3+4j) # 5.0 (\u8fd4\u56de\u6a21)<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nabs(float('inf')) # inf
\nabs(float('-inf')) # inf
\nabs(float('nan')) # nan<\/p>\n
\u8fd4\u56de\u53ef\u8fed\u4ee3\u5bf9\u8c61\u4e2d\u7684\u6700\u5927\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nmax([1, 2, 3]) # 3
\nmax('a', 'b', 'c') # 'c'<\/p>\n
# \u6307\u5b9akey\u51fd\u6570
\nmax(['apple', 'banana', 'cherry'], key=len) # 'banana'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nmax([]) # ValueError: max() arg is an empty sequence
\nmax([float('nan'), 1, 2]) # nan (\u4f46\u6bd4\u8f83nan\u7684\u884c\u4e3a\u53ef\u80fd\u4e0d\u4e00\u81f4)
\nmax([None, 1, 2]) # TypeError: '>' not supported between instances of 'int' and 'NoneType'<\/p>\n
\u8fd4\u56de\u53ef\u8fed\u4ee3\u5bf9\u8c61\u4e2d\u7684\u6700\u5c0f\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nmin([1, 2, 3]) # 1
\nmin('a', 'b', 'c') # 'a'<\/p>\n
# \u6307\u5b9akey\u51fd\u6570
\nmin(['apple', 'banana', 'cherry'], key=len) # 'apple'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nmin([]) # ValueError: min() arg is an empty sequence
\nmin([float('nan'), 1, 2]) # nan (\u4f46\u6bd4\u8f83nan\u7684\u884c\u4e3a\u53ef\u80fd\u4e0d\u4e00\u81f4)
\nmin([None, 1, 2]) # TypeError: '<' not supported between instances of 'int' and 'NoneType'<\/p>\n
\u5bf9\u53ef\u8fed\u4ee3\u5bf9\u8c61\u4e2d\u7684\u5143\u7d20\u6c42\u548c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nsum([1, 2, 3]) # 6
\nsum([1.5, 2.5, 3]) # 7.0<\/p>\n
# \u6307\u5b9a\u8d77\u59cb\u503c
\nsum([1, 2, 3], 10) # 16<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nsum([]) # 0
\nsum(['a', 'b']) # TypeError: unsupported operand type(s) for +: 'int' and 'str'
\nsum([float('inf'), 1]) # inf
\nsum([float('nan'), 1]) # nan<\/p>\n
\u5bf9\u6d6e\u70b9\u6570\u8fdb\u884c\u56db\u820d\u4e94\u5165\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nround(3.14159) # 3
\nround(3.14159, 2) # 3.14<\/p>\n
# \u94f6\u884c\u5bb6\u820d\u5165\u6cd5(\u56db\u820d\u516d\u5165\u4e94\u6210\u53cc)
\nround(2.5) # 2
\nround(3.5) # 4<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nround(float('inf')) # inf
\nround(float('nan')) # nan
\nround(123.456, -2) # 100.0 (\u8d1f\u7684ndigits\u53c2\u6570)
\nround(123.456, 300) # 123.456 (\u8fc7\u5927ndigits\u53c2\u6570)<\/p>\n
\u8fd4\u56de\u5bf9\u8c61\u7684\u957f\u5ea6\u6216\u5143\u7d20\u4e2a\u6570\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlen('abc') # 3
\nlen([1,2,3]) # 3
\nlen({'a':1}) # 1<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlen('') # 0
\nlen(None) # TypeError: object of type 'NoneType' has no len()
\nlen(123) # TypeError: object of type 'int' has no len()<\/p>\n
\u4ee5\u6307\u5b9a\u5b57\u7b26\u4e3a\u5206\u9694\u7b26\u5206\u5272\u5b57\u7b26\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n'apple,banana,cherry'.split(',') # ['apple', 'banana', 'cherry']<\/p>\n
# \u6307\u5b9a\u6700\u5927\u5206\u5272\u6b21\u6570
\n'apple,banana,cherry'.split(',', 1) # ['apple', 'banana,cherry']<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n''.split(',') # ['']
\n' '.split() # [] (\u9ed8\u8ba4\u5206\u5272\u7a7a\u767d\u5b57\u7b26)
\nNone.split() # AttributeError: 'NoneType' object has no attribute 'split'<\/p>\n
\u7528\u6307\u5b9a\u5b57\u7b26\u4e32\u8fde\u63a5\u53ef\u8fed\u4ee3\u5bf9\u8c61\u4e2d\u7684\u5b57\u7b26\u4e32\u5143\u7d20\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n','.join(['a', 'b', 'c']) # 'a,b,c'
\n'-'.join('abc') # 'a-b-c'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n''.join([]) # ''
\n','.join([1, 2, 3]) # TypeError: sequence item 0: expected str instance, int found
\n','.join(None) # TypeError: can only join an iterable<\/p>\n
\u5728\u5b57\u7b26\u4e32\u4e2d\u67e5\u627e\u5b50\u4e32，\u8fd4\u56de\u9996\u6b21\u51fa\u73b0\u7684\u7d22\u5f15\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n'hello world'.find('world') # 6
\n'hello world'.find('o') # 4<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n'hello'.find('x') # -1 (\u672a\u627e\u5230)
\n''.find('') # 0
\n'hello'.find('') # 0
\n'hello'.find(None) # TypeError: must be str, not NoneType<\/p>\n
\u4ece\u53f3\u4fa7\u5f00\u59cb\u67e5\u627e\u5b50\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n'hello world'.rfind('o') # 7<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n'hello'.rfind('x') # -1
\n''.rfind('') # 0
\n'hello'.rfind('', 10) # 5 (\u8d85\u8fc7\u5b57\u7b26\u4e32\u957f\u5ea6)<\/p>\n
\u66ff\u6362\u5b57\u7b26\u4e32\u4e2d\u7684\u6307\u5b9a\u5b50\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n'hello world'.replace('world', 'Python') # 'hello Python'<\/p>\n
# \u6307\u5b9a\u66ff\u6362\u6b21\u6570
\n'ababab'.replace('a', 'c', 2) # 'cbcbab'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n'hello'.replace('', '-') # '-h-e-l-l-o-'
\n'hello'.replace('x', 'y') # 'hello' (\u65e0\u5339\u914d)
\n'hello'.replace(None, 'y') # TypeError: replace() argument 1 must be str, not NoneType<\/p>\n
\u53bb\u9664\u5b57\u7b26\u4e32\u4e24\u7aef\u7684\u7a7a\u767d\u5b57\u7b26\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n' hello '.strip() # 'hello'
\n'\\\\thello\\\\n'.strip() # 'hello'<\/p>\n
# \u6307\u5b9a\u53bb\u9664\u5b57\u7b26
\n'xxhelloxx'.strip('x') # 'hello'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n''.strip() # ''
\n' '.strip() # ''
\nNone.strip() # AttributeError<\/p>\n
\u53bb\u9664\u5b57\u7b26\u4e32\u5de6\u4fa7\u7684\u7a7a\u767d\u5b57\u7b26\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n' hello '.lstrip() # 'hello '<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n''.lstrip() # ''
\nNone.lstrip() # AttributeError<\/p>\n
\u53bb\u9664\u5b57\u7b26\u4e32\u53f3\u4fa7\u7684\u7a7a\u767d\u5b57\u7b26\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n' hello '.rstrip() # ' hello'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n''.rstrip() # ''
\nNone.rstrip() # AttributeError<\/p>\n
\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u5927\u5199\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n'Hello'.upper() # 'HELLO'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n''.upper() # ''
\n'123'.upper() # '123'
\nNone.upper() # AttributeError<\/p>\n
\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u5c0f\u5199\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n'Hello'.lower() # 'hello'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n''.lower() # ''
\n'123'.lower() # '123'
\nNone.lower() # AttributeError<\/p>\n
\u5c06\u6bcf\u4e2a\u5355\u8bcd\u7684\u9996\u5b57\u6bcd\u5927\u5199\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n'hello world'.title() # 'Hello World'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n''.title() # ''
\n"they're bill's".title() # "They'Re Bill'S" (\u6ce8\u610f\u6487\u53f7\u540e\u7684\u5b57\u6bcd)
\nNone.title() # AttributeError<\/p>\n
\u5728\u5217\u8868\u672b\u5c3e\u6dfb\u52a0\u5143\u7d20\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [1, 2]
\nlst.append(3) # lst\u53d8\u4e3a[1, 2, 3]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlst.append(None) # lst\u53d8\u4e3a[1, 2, 3, None]
\nlst.append(lst) # \u53ef\u4ee5\u6dfb\u52a0\u81ea\u8eab(\u521b\u5efa\u5faa\u73af\u5f15\u7528)<\/p>\n
\u7528\u53ef\u8fed\u4ee3\u5bf9\u8c61\u6269\u5c55\u5217\u8868\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [1, 2]
\nlst.extend([3, 4]) # lst\u53d8\u4e3a[1, 2, 3, 4]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlst.extend('abc') # lst\u53d8\u4e3a[1, 2, 3, 4, 'a', 'b', 'c']
\nlst.extend(None) # TypeError: 'NoneType' object is not iterable<\/p>\n
\u5728\u6307\u5b9a\u4f4d\u7f6e\u63d2\u5165\u5143\u7d20\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [1, 3]
\nlst.insert(1, 2) # lst\u53d8\u4e3a[1, 2, 3]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlst.insert(-10, 0) # \u63d2\u5165\u5230\u6700\u524d\u9762
\nlst.insert(100, 4) # \u63d2\u5165\u5230\u6700\u540e\u9762
\nlst.insert(1, None) # \u53ef\u4ee5\u63d2\u5165None<\/p>\n
\u79fb\u9664\u5217\u8868\u4e2d\u6307\u5b9a\u503c\u7684\u7b2c\u4e00\u4e2a\u5339\u914d\u9879\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [1, 2, 3, 2]
\nlst.remove(2) # lst\u53d8\u4e3a[1, 3, 2]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlst.remove(4) # ValueError: list.remove(x): x not in list
\nlst.remove(None) # \u5982\u679c\u5217\u8868\u4e2d\u6709None\u53ef\u4ee5\u79fb\u9664<\/p>\n
\u79fb\u9664\u5e76\u8fd4\u56de\u6307\u5b9a\u4f4d\u7f6e\u7684\u5143\u7d20\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [1, 2, 3]
\nlst.pop() # \u8fd4\u56de3, lst\u53d8\u4e3a[1, 2]
\nlst.pop(0) # \u8fd4\u56de1, lst\u53d8\u4e3a[2]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlst.pop(100) # IndexError: pop index out of range
\n[].pop() # IndexError: pop from empty list<\/p>\n
\u8fd4\u56de\u6307\u5b9a\u5143\u7d20\u7684\u7d22\u5f15\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [1, 2, 3, 2]
\nlst.index(2) # 1<\/p>\n
# \u6307\u5b9a\u641c\u7d22\u8303\u56f4
\nlst.index(2, 2) # 3<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlst.index(4) # ValueError: 4 is not in list
\n[].index(1) # ValueError: 1 is not in list<\/p>\n
\u8fd4\u56de\u6307\u5b9a\u5143\u7d20\u7684\u51fa\u73b0\u6b21\u6570\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [1, 2, 3, 2]
\nlst.count(2) # 2<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlst.count(4) # 0
\n[].count(1) # 0
\nlst.count(None) # 0 (\u9664\u975e\u5217\u8868\u4e2d\u6709None)<\/p>\n
\u5bf9\u5217\u8868\u8fdb\u884c\u539f\u5730\u6392\u5e8f\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [3, 1, 2]
\nlst.sort() # lst\u53d8\u4e3a[1, 2, 3]<\/p>\n
# \u6307\u5b9akey\u548creverse
\nlst.sort(reverse=True) # \u964d\u5e8f\u6392\u5e8f
\nlst.sort(key=lambda x: -x) # \u6309\u8d1f\u503c\u6392\u5e8f<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlst = [1, 'a', 2] # TypeError: '<' not supported between instances of 'str' and 'int'
\n[].sort() # \u65e0\u64cd\u4f5c<\/p>\n
\u53cd\u8f6c\u5217\u8868\u4e2d\u7684\u5143\u7d20\u987a\u5e8f\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlst = [1, 2, 3]
\nlst.reverse() # lst\u53d8\u4e3a[3, 2, 1]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n[].reverse() # \u65e0\u64cd\u4f5c<\/p>\n
\u8fd4\u56de\u5b57\u5178\u7684\u952e\u89c6\u56fe\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nd = {'a':1, 'b':2}
\nd.keys() # dict_keys(['a', 'b'])<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n{}.keys() # dict_keys([])<\/p>\n
\u8fd4\u56de\u5b57\u5178\u7684\u503c\u89c6\u56fe\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nd = {'a':1, 'b':2}
\nd.values() # dict_values([1, 2])<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n{}.values() # dict_values([])<\/p>\n
\u8fd4\u56de\u5b57\u5178\u7684\u952e\u503c\u5bf9\u89c6\u56fe\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nd = {'a':1, 'b':2}
\nd.items() # dict_items([('a', 1), ('b', 2)])<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n{}.items() # dict_items([])<\/p>\n
\u83b7\u53d6\u6307\u5b9a\u952e\u7684\u503c，\u4e0d\u5b58\u5728\u5219\u8fd4\u56de\u9ed8\u8ba4\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nd = {'a':1, 'b':2}
\nd.get('a') # 1
\nd.get('c', 0) # 0<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nd.get('c') # None (\u4e0d\u6307\u5b9a\u9ed8\u8ba4\u503c\u65f6)<\/p>\n
\u79fb\u9664\u5e76\u8fd4\u56de\u6307\u5b9a\u952e\u7684\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nd = {'a':1, 'b':2}
\nd.pop('a') # 1, d\u53d8\u4e3a{'b':2}<\/p>\n
# \u6307\u5b9a\u9ed8\u8ba4\u503c
\nd.pop('c', 0) # 0<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nd.pop('c') # KeyError: 'c'
\n{}.pop('a') # KeyError: 'a'<\/p>\n
\u968f\u673a\u79fb\u9664\u5e76\u8fd4\u56de\u4e00\u4e2a\u952e\u503c\u5bf9\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nd = {'a':1, 'b':2}
\nd.popitem() # \u53ef\u80fd\u662f ('a', 1) \u6216 ('b', 2)<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n{}.popitem() # KeyError: 'popitem(): dictionary is empty'<\/p>\n
\u7528\u53e6\u4e00\u4e2a\u5b57\u5178\u66f4\u65b0\u5f53\u524d\u5b57\u5178\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nd = {'a':1}
\nd.update({'b':2}) # d\u53d8\u4e3a{'a':1, 'b':2}<\/p>\n
# \u591a\u79cd\u66f4\u65b0\u65b9\u5f0f
\nd.update(b=3, c=4) # d\u53d8\u4e3a{'a':1, 'b':3, 'c':4}<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nd.update(None) # TypeError: 'NoneType' object is not iterable
\nd.update(1) # TypeError: cannot convert dictionary update sequence element #0 to a sequence<\/p>\n
\u6253\u5f00\u6587\u4ef6\u5e76\u8fd4\u56de\u6587\u4ef6\u5bf9\u8c61\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# f = open('file.txt', 'r') # \u4ee5\u53ea\u8bfb\u65b9\u5f0f\u6253\u5f00\u6587\u4ef6<\/p>\n
# \u5e38\u7528\u6a21\u5f0f
\n# 'r' – \u8bfb\u53d6 (\u9ed8\u8ba4)
\n# 'w' – \u5199\u5165 (\u4f1a\u622a\u65ad\u6587\u4ef6)
\n# 'a' – \u8ffd\u52a0
\n# 'b' – \u4e8c\u8fdb\u5236\u6a21\u5f0f
\n# '+' – \u8bfb\u5199\u6a21\u5f0f<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# open('nonexistent.txt', 'r') # FileNotFoundError
\n# open('\/invalid\/path', 'w') # PermissionError \u6216\u5176\u4ed6OSError<\/p>\n
\u8bfb\u53d6\u6587\u4ef6\u5185\u5bb9\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# with open('file.txt') as f:
\n# content = f.read() # \u8bfb\u53d6\u5168\u90e8\u5185\u5bb9<\/p>\n
# \u6307\u5b9a\u8bfb\u53d6\u5927\u5c0f
\n# f.read(100) # \u8bfb\u53d6100\u4e2a\u5b57\u7b26<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# f.read() \u5728\u6587\u4ef6\u5173\u95ed\u540e\u8c03\u7528\u4f1a\u5f15\u53d1 ValueError<\/p>\n
\u8bfb\u53d6\u6587\u4ef6\u7684\u4e00\u884c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# with open('file.txt') as f:
\n# line = f.readline() # \u8bfb\u53d6\u4e00\u884c<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u6587\u4ef6\u672b\u5c3e\u8fd4\u56de\u7a7a\u5b57\u7b26\u4e32 ''<\/p>\n
\u8bfb\u53d6\u6240\u6709\u884c\u5e76\u8fd4\u56de\u5217\u8868\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# with open('file.txt') as f:
\n# lines = f.readlines() # \u8fd4\u56de\u884c\u5217\u8868<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u7a7a\u6587\u4ef6\u8fd4\u56de\u7a7a\u5217\u8868 []<\/p>\n
\u5c06\u5b57\u7b26\u4e32\u5199\u5165\u6587\u4ef6\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# with open('file.txt', 'w') as f:
\n# f.write('hello\\\\n') # \u5199\u5165\u5b57\u7b26\u4e32<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u53ea\u80fd\u5199\u5165\u5b57\u7b26\u4e32，\u5199\u5165\u5176\u4ed6\u7c7b\u578b\u4f1a\u5f15\u53d1 TypeError
\n# f.write(123) # TypeError<\/p>\n
\u5173\u95ed\u6587\u4ef6\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# f = open('file.txt')
\n# f.close()<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u591a\u6b21\u8c03\u7528close()\u4e0d\u4f1a\u62a5\u9519
\n# \u4f7f\u7528with\u8bed\u53e5\u66f4\u5b89\u5168，\u4f1a\u81ea\u52a8\u5173\u95ed\u6587\u4ef6<\/p>\n
\u751f\u6210\u6574\u6570\u5e8f\u5217\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlist(range(5)) # [0, 1, 2, 3, 4]
\nlist(range(1, 5)) # [1, 2, 3, 4]
\nlist(range(1, 10, 2)) # [1, 3, 5, 7, 9]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlist(range(0)) # []
\nlist(range(1, 1)) # []
\nlist(range(1, 5, -1)) # []<\/p>\n
\u8fd4\u56de\u679a\u4e3e\u5bf9\u8c61(\u7d22\u5f15\u548c\u5143\u7d20)\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlist(enumerate(['a', 'b', 'c'])) # [(0, 'a'), (1, 'b'), (2, 'c')]<\/p>\n
# \u6307\u5b9a\u8d77\u59cb\u7d22\u5f15
\nlist(enumerate(['a', 'b'], 1)) # [(1, 'a'), (2, 'b')]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlist(enumerate([])) # []
\nlist(enumerate(None)) # TypeError: 'NoneType' object is not iterable<\/p>\n
\u5c06\u591a\u4e2a\u53ef\u8fed\u4ee3\u5bf9\u8c61\u6253\u5305\u6210\u5143\u7ec4\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlist(zip([1, 2], ['a', 'b'])) # [(1, 'a'), (2, 'b')]<\/p>\n
# \u4e0d\u540c\u957f\u5ea6\u5904\u7406
\nlist(zip([1, 2, 3], ['a', 'b'])) # [(1, 'a'), (2, 'b')]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlist(zip()) # []
\nlist(zip([], [])) # []
\nlist(zip([1], None)) # TypeError: zip argument #2 must support iteration<\/p>\n
\u5c06\u51fd\u6570\u5e94\u7528\u4e8e\u53ef\u8fed\u4ee3\u5bf9\u8c61\u7684\u6bcf\u4e2a\u5143\u7d20\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlist(map(str, [1, 2, 3])) # ['1', '2', '3']
\nlist(map(lambda x: x*2, [1, 2, 3])) # [2, 4, 6]<\/p>\n
# \u591a\u4e2a\u53ef\u8fed\u4ee3\u5bf9\u8c61
\nlist(map(lambda x,y: x+y, [1,2], [3,4])) # [4, 6]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlist(map(str, [])) # []
\nlist(map(None, [1,2])) # TypeError: 'NoneType' object is not callable<\/p>\n
\u6839\u636e\u51fd\u6570\u6761\u4ef6\u8fc7\u6ee4\u5143\u7d20\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlist(filter(lambda x: x>0, [-1, 0, 1, 2])) # [1, 2]<\/p>\n
# \u4f7f\u7528None\u8fc7\u6ee4\u5047\u503c
\nlist(filter(None, [0, 1, False, True])) # [1, True]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlist(filter(lambda x: x>0, [])) # []<\/p>\n
\u5bf9\u5143\u7d20\u8fdb\u884c\u7d2f\u79ef\u8ba1\u7b97(\u9700\u4ecefunctools\u5bfc\u5165)\u3002<\/p>\n
from functools import reduce<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nreduce(lambda x,y: x+y, [1,2,3,4]) # 10 (((1+2)+3)+4)<\/p>\n
# \u6307\u5b9a\u521d\u59cb\u503c
\nreduce(lambda x,y: x+y, [1,2,3], 10) # 16<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nreduce(lambda x,y: x+y, []) # TypeError: reduce() of empty sequence with no initial value
\nreduce(lambda x,y: x+y, [1]) # 1 (\u5355\u5143\u7d20\u76f4\u63a5\u8fd4\u56de)<\/p>\n
\u5bfc\u5165\u6a21\u5757\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# import math
\n# math.sqrt(4)<\/p>\n
# \u522b\u540d
\n# import numpy as np<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# import nonexistent_module # ModuleNotFoundError<\/p>\n
\u4ece\u6a21\u5757\u5bfc\u5165\u7279\u5b9a\u5bf9\u8c61\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# from math import sqrt
\n# sqrt(4)<\/p>\n
# \u5bfc\u5165\u591a\u4e2a
\n# from math import sqrt, pi<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# from math import nonexistent # ImportError: cannot import name 'nonexistent'<\/p>\n
\u83b7\u53d6\u5f53\u524d\u65e5\u671f\u3002<\/p>\n
from datetime import date<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# today = date.today() # \u8fd4\u56dedate\u5bf9\u8c61<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u65e0\u53c2\u6570，\u603b\u662f\u8fd4\u56de\u5f53\u524d\u65e5\u671f<\/p>\n
\u83b7\u53d6\u5f53\u524d\u65e5\u671f\u548c\u65f6\u95f4\u3002<\/p>\n
from datetime import datetime<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# now = datetime.now() # \u8fd4\u56dedatetime\u5bf9\u8c61<\/p>\n
# \u6307\u5b9a\u65f6\u533a
\n# from datetime import timezone
\n# datetime.now(timezone.utc)<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u65e0\u53c2\u6570，\u603b\u662f\u8fd4\u56de\u5f53\u524d\u65f6\u95f4<\/p>\n
\u5c06\u5b57\u7b26\u4e32\u89e3\u6790\u4e3a\u65e5\u671f\u65f6\u95f4\u5bf9\u8c61\u3002<\/p>\n
from datetime import datetime<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# dt = datetime.strptime('2023-01-01', '%Y-%m-%d')<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# datetime.strptime('invalid', '%Y') # ValueError: time data 'invalid' does not match format '%Y'
\n# datetime.strptime(None, '%Y') # TypeError: strptime() argument 1 must be str, not None<\/p>\n
\u5c06\u65e5\u671f\u65f6\u95f4\u5bf9\u8c61\u683c\u5f0f\u5316\u4e3a\u5b57\u7b26\u4e32\u3002<\/p>\n
from datetime import datetime<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# now = datetime.now()
\n# now.strftime('%Y-%m-%d %H:%M:%S')<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# datetime.strftime(None, '%Y') # AttributeError: 'NoneType' object has no attribute 'strftime'<\/p>\n
\u6355\u83b7\u548c\u5904\u7406\u5f02\u5e38\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\ntry:
\n 1 \/ 0
\nexcept ZeroDivisionError:
\n print("\u4e0d\u80fd\u9664\u4ee5\u96f6")<\/p>\n
# \u591a\u4e2a\u5f02\u5e38
\ntry:
\n # \u53ef\u80fd\u51fa\u9519\u7684\u4ee3\u7801
\nexcept (TypeError, ValueError):
\n # \u5904\u7406\u591a\u79cd\u5f02\u5e38
\nexcept Exception as e:
\n # \u6355\u83b7\u6240\u6709\u5f02\u5e38
\n print(f"\u53d1\u751f\u9519\u8bef: {e}")
\nfinally:
\n # \u65e0\u8bba\u662f\u5426\u53d1\u751f\u5f02\u5e38\u90fd\u4f1a\u6267\u884c
\n print("\u6e05\u7406\u4ee3\u7801")<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u7a7a\u7684try-except\u5757\u662f\u5408\u6cd5\u4f46\u4e0d\u597d\u7684\u505a\u6cd5<\/p>\n
\u624b\u52a8\u629b\u51fa\u5f02\u5e38\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nif x < 0:
\n raise ValueError("x\u4e0d\u80fd\u4e3a\u8d1f\u6570")<\/p>\n
# \u91cd\u65b0\u629b\u51fa\u5f53\u524d\u5f02\u5e38
\ntry:
\n 1 \/ 0
\nexcept:
\n print("\u53d1\u751f\u9519\u8bef")
\n raise # \u91cd\u65b0\u629b\u51fa<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nraise # \u4e0d\u5728except\u5757\u4e2d\u4f7f\u7528\u4f1a\u5f15\u53d1RuntimeError
\nraise None # TypeError: exceptions must derive from BaseException<\/p>\n
\u8fd4\u56de\u5bf9\u8c61\u7684\u552f\u4e00\u6807\u8bc6\u7b26\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nx = 1
\nid(x) # \u8fd4\u56de\u5185\u5b58\u5730\u5740<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nid(None) # \u8fd4\u56deNone\u7684id<\/p>\n
\u8fd4\u56de\u5bf9\u8c61\u7684\u7c7b\u578b\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\ntype(1) # <class 'int'>
\ntype('a') # <class 'str'><\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\ntype(None) # <class 'NoneType'>
\ntype(type) # <class 'type'><\/p>\n
\u68c0\u67e5\u5bf9\u8c61\u662f\u5426\u662f\u7c7b\u7684\u5b9e\u4f8b\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nisinstance(1, int) # True
\nisinstance('a', str) # True<\/p>\n
# \u68c0\u67e5\u591a\u4e2a\u7c7b\u578b
\nisinstance(1, (int, float)) # True<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nisinstance(1, type) # False
\nisinstance(int, type) # True<\/p>\n
\u68c0\u67e5\u5bf9\u8c61\u662f\u5426\u6709\u6307\u5b9a\u5c5e\u6027\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nhasattr('abc', 'upper') # True<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nhasattr(None, 'x') # False
\nhasattr(1, 'imag') # True (int\u6709imag\u5c5e\u6027)<\/p>\n
\u8bbe\u7f6e\u5bf9\u8c61\u7684\u5c5e\u6027\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nclass MyClass: pass
\nobj = MyClass()
\nsetattr(obj, 'x', 1) # obj.x = 1<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nsetattr(1, 'x', 1) # TypeError: 'int' object has no attribute 'x'
\nsetattr(obj, 123, 1) # \u5c5e\u6027\u540d\u5e94\u4e3a\u5b57\u7b26\u4e32<\/p>\n
\u83b7\u53d6\u5bf9\u8c61\u7684\u5c5e\u6027\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\ngetattr('abc', 'upper')() # 'ABC'<\/p>\n
# \u6307\u5b9a\u9ed8\u8ba4\u503c
\ngetattr('abc', 'x', None) # None<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\ngetattr('abc', 123) # TypeError: attribute name must be string<\/p>\n
\u5220\u9664\u5bf9\u8c61\u7684\u5c5e\u6027\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nclass MyClass: x = 1
\nobj = MyClass()
\ndelattr(obj, 'x')<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\ndelattr(obj, 'x') # AttributeError: x
\ndelattr(1, 'real') # TypeError: 'int' object has no attribute 'real'<\/p>\n
\u8fd4\u56de\u5168\u5c40\u53d8\u91cf\u7684\u5b57\u5178\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nglobals() # \u8fd4\u56de\u5f53\u524d\u5168\u5c40\u7b26\u53f7\u8868<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u603b\u662f\u8fd4\u56de\u5b57\u5178，\u5373\u4f7f\u5728\u51fd\u6570\u5185\u90e8<\/p>\n
\u8fd4\u56de\u5c40\u90e8\u53d8\u91cf\u7684\u5b57\u5178\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\ndef func():
\n x = 1
\n return locals()<\/p>\n
func() # {'x': 1}<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u5728\u6a21\u5757\u7ea7\u522b，locals()\u548cglobals()\u76f8\u540c<\/p>\n
\u542f\u52a8\u5e2e\u52a9\u7cfb\u7edf\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\n# help(list) # \u663e\u793alist\u7684\u5e2e\u52a9\u4fe1\u606f<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# help(None) # \u663e\u793aNone\u7684\u5e2e\u52a9\u4fe1\u606f<\/p>\n
\u8fd4\u56de\u5bf9\u8c61\u7684\u5c5e\u6027\u5217\u8868\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\ndir(list) # \u8fd4\u56delist\u7684\u5c5e\u6027\u548c\u65b9\u6cd5\u5217\u8868<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\ndir() # \u8fd4\u56de\u5f53\u524d\u4f5c\u7528\u57df\u7684\u53d8\u91cf\u540d
\ndir(None) # \u8fd4\u56deNone\u7684\u5c5e\u6027\u548c\u65b9\u6cd5\u5217\u8868<\/p>\n
\u5c06\u5b57\u7b26\u4e32\u7f16\u8bd1\u4e3a\u4ee3\u7801\u5bf9\u8c61\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\ncode = compile('print("hello")', 'test', 'exec')
\nexec(code) # \u8f93\u51fahello<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\ncompile('invalid code', 'test', 'exec') # SyntaxError
\ncompile(123, 'test', 'exec') # TypeError: expected string without null bytes<\/p>\n
\u8ba1\u7b97\u5b57\u7b26\u4e32\u8868\u8fbe\u5f0f\u7684\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\neval('1 + 1') # 2<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\neval('import os') # SyntaxError
\neval(None) # TypeError: eval() arg 1 must be a string, bytes or code object<\/p>\n
\u6267\u884c\u5b57\u7b26\u4e32\u6216\u4ee3\u7801\u5bf9\u8c61\u4e2d\u7684\u4ee3\u7801\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nexec('x = 1\\\\nprint(x)') # \u8f93\u51fa1<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nexec(None) # TypeError: exec() arg 1 must be a string, bytes or code object<\/p>\n
\u8fd4\u56de\u5bf9\u8c61\u7684\u54c8\u5e0c\u503c\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nhash('abc') # \u8fd4\u56de\u54c8\u5e0c\u503c<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nhash([]) # TypeError: unhashable type: 'list'
\nhash(None) # \u8fd4\u56deNone\u7684\u54c8\u5e0c\u503c<\/p>\n
\u8fd4\u56de\u8fed\u4ee3\u5668\u5bf9\u8c61\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nit = iter([1, 2, 3])
\nnext(it) # 1<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\niter(1) # TypeError: 'int' object is not iterable
\niter(None) # TypeError: 'NoneType' object is not iterable<\/p>\n
\u83b7\u53d6\u8fed\u4ee3\u5668\u7684\u4e0b\u4e00\u4e2a\u5143\u7d20\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nit = iter([1, 2])
\nnext(it) # 1<\/p>\n
# \u6307\u5b9a\u9ed8\u8ba4\u503c
\nnext(it, 'end') # 2
\nnext(it, 'end') # 'end'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nnext(it) # StopIteration<\/p>\n
\u68c0\u67e5\u53ef\u8fed\u4ee3\u5bf9\u8c61\u4e2d\u7684\u6240\u6709\u5143\u7d20\u662f\u5426\u4e3a\u771f\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nall([1, 2, 3]) # True
\nall([1, 0, 3]) # False<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nall([]) # True (\u7a7a\u53ef\u8fed\u4ee3\u5bf9\u8c61)
\nall([None]) # False<\/p>\n
\u68c0\u67e5\u53ef\u8fed\u4ee3\u5bf9\u8c61\u4e2d\u662f\u5426\u6709\u4efb\u4f55\u5143\u7d20\u4e3a\u771f\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nany([0, 1, 0]) # True
\nany([0, 0, 0]) # False<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nany([]) # False (\u7a7a\u53ef\u8fed\u4ee3\u5bf9\u8c61)
\nany([None]) # False<\/p>\n
\u521b\u5efa\u5b57\u8282\u5bf9\u8c61\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nbytes([1, 2, 3]) # b'\\\\x01\\\\x02\\\\x03'
\nbytes('abc', 'utf-8') # b'abc'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nbytes(-1) # ValueError: negative count
\nbytes('abc', 'invalid') # LookupError: unknown encoding: invalid<\/p>\n
\u521b\u5efa\u53ef\u53d8\u7684\u5b57\u8282\u6570\u7ec4\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nbytearray([1, 2, 3]) # bytearray(b'\\\\x01\\\\x02\\\\x03')<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nbytearray(-1) # ValueError: negative count<\/p>\n
\u8fd4\u56de\u5bf9\u8c61\u7684\u5185\u5b58\u89c6\u56fe\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nmv = memoryview(b'abc')
\nmv[0] # 97<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nmemoryview('abc') # TypeError: memoryview: a bytes-like object is required<\/p>\n
\u8fd4\u56de\u5b57\u7b26\u7684Unicode\u7801\u70b9\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nord('a') # 97<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nord('') # TypeError: ord() expected a character, but string of length 0 found
\nord('ab') # TypeError: ord() expected a character, but string of length 2 found<\/p>\n
\u6839\u636eUnicode\u7801\u70b9\u8fd4\u56de\u5b57\u7b26\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nchr(97) # 'a'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nchr(-1) # ValueError: chr() arg not in range(0x110000)
\nchr(0x110000) # ValueError<\/p>\n
\u5c06\u6574\u6570\u8f6c\u6362\u4e3a\u4e8c\u8fdb\u5236\u5b57\u7b26\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nbin(10) # '0b1010'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nbin(3.14) # TypeError: 'float' object cannot be interpreted as an integer
\nbin(-10) # '-0b1010'<\/p>\n
\u5c06\u6574\u6570\u8f6c\u6362\u4e3a\u516b\u8fdb\u5236\u5b57\u7b26\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\noct(8) # '0o10'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\noct(3.14) # TypeError
\noct(-8) # '-0o10'<\/p>\n
\u5c06\u6574\u6570\u8f6c\u6362\u4e3a\u5341\u516d\u8fdb\u5236\u5b57\u7b26\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nhex(16) # '0x10'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nhex(3.14) # TypeError
\nhex(-16) # '-0x10'<\/p>\n
\u521b\u5efa\u4e0d\u53ef\u53d8\u96c6\u5408\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nfs = frozenset([1, 2, 3])<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nfrozenset(None) # TypeError: 'NoneType' object is not iterable<\/p>\n
\u8c03\u7528\u7236\u7c7b\u65b9\u6cd5\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nclass Parent:
\n def method(self):
\n print("Parent method")<\/p>\n
class Child(Parent):
\n def method(self):
\n super().method()
\n print("Child method")<\/p>\n
Child().method()
\n# \u8f93\u51fa:
\n# Parent method
\n# Child method<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u4e0d\u6b63\u786e\u7684\u4f7f\u7528\u4f1a\u5bfc\u81f4RuntimeError<\/p>\n
\u521b\u5efa\u5c5e\u6027\u63cf\u8ff0\u7b26\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nclass MyClass:
\n def __init__(self):
\n self._x = None<\/p>\n
@property
\n def x(self):
\n return self._x<\/p>\n
@x.setter
\n def x(self, value):
\n self._x = value<\/p>\n
obj = MyClass()
\nobj.x = 1 # \u8c03\u7528setter
\nprint(obj.x) # \u8c03\u7528getter<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u4e0d\u6b63\u786e\u7684\u5c5e\u6027\u8bbf\u95ee\u4f1a\u5f15\u53d1AttributeError<\/p>\n
\u5b9a\u4e49\u7c7b\u65b9\u6cd5\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nclass MyClass:
\n @classmethod
\n def class_method(cls):
\n print(f"Called from {cls}")<\/p>\n
MyClass.class_method() # \u901a\u8fc7\u7c7b\u8c03\u7528
\nobj = MyClass()
\nobj.class_method() # \u901a\u8fc7\u5b9e\u4f8b\u8c03\u7528<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u4e0d\u6b63\u786e\u7684\u4f7f\u7528\u4f1a\u5bfc\u81f4TypeError<\/p>\n
\u5b9a\u4e49\u9759\u6001\u65b9\u6cd5\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nclass MyClass:
\n @staticmethod
\n def static_method():
\n print("Static method")<\/p>\n
MyClass.static_method() # \u901a\u8fc7\u7c7b\u8c03\u7528
\nobj = MyClass()
\nobj.static_method() # \u901a\u8fc7\u5b9e\u4f8b\u8c03\u7528<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\n# \u4e0d\u6b63\u786e\u7684\u4f7f\u7528\u4f1a\u5bfc\u81f4TypeError<\/p>\n
\u8fd4\u56de\u5bf9\u8c61\u7684\u957f\u5ea6\u6216\u5143\u7d20\u4e2a\u6570\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlen('abc') # 3
\nlen([1,2,3]) # 3<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlen(123) # TypeError
\nlen(None) # TypeError<\/p>\n
\u5bf9\u53ef\u8fed\u4ee3\u5bf9\u8c61\u8fdb\u884c\u6392\u5e8f\u5e76\u8fd4\u56de\u65b0\u5217\u8868\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nsorted([3, 1, 2]) # [1, 2, 3]<\/p>\n
# \u6307\u5b9akey\u548creverse
\nsorted(['apple', 'banana'], key=len, reverse=True) # ['banana', 'apple']<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nsorted(None) # TypeError
\nsorted([1, 'a']) # TypeError<\/p>\n
\u8fd4\u56de\u53cd\u8f6c\u7684\u8fed\u4ee3\u5668\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nlist(reversed([1, 2, 3])) # [3, 2, 1]<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nlist(reversed(None)) # TypeError
\nlist(reversed(123)) # TypeError<\/p>\n
\u683c\u5f0f\u5316\u5b57\u7b26\u4e32\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nformat(3.14159, '.2f') # '3.14'
\n"{:.2f}".format(3.14159) # '3.14'<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nformat('abc', 123) # TypeError<\/p>\n
\u8fd4\u56de\u5bf9\u8c61\u7684\u5c5e\u6027\u5b57\u5178\u3002<\/p>\n
# \u57fa\u672c\u7528\u6cd5
\nclass MyClass: pass
\nobj = MyClass()
\nobj.x = 1
\nvars(obj) # {'x': 1}<\/p>\n
# \u4e34\u754c\u503c\u5904\u7406
\nvars(1) # TypeError
\nvars(None) # TypeError<\/p>\n","protected":false},"excerpt":{"rendered":"
\u6587\u7ae0\u6d4f\u89c8\u9605\u8bfb2.7k\u6b21\uff0c\u70b9\u8d5e48\u6b21\uff0c\u6536\u85cf123\u6b21\u3002Python 100\u4e2a\u5e38\u7528\u51fd\u6570\u5168\u9762\u89e3\u6790<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[81,190],"topic":[],"class_list":["post-44114","post","type-post","status-publish","format-standard","hentry","category-server","tag-python","tag-190"],"yoast_head":"\n