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Multiple aggregations of the same column using pandas GroupBy.agg()

... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers. Draft saved Draft discarded ...
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【解决】scrapyd启动job时报错:exceptions.TypeError: __init__() got an ...

【解决】scrapyd启动job时报错:exceptions.TypeError: __init__() got an unexpected keyword argument '_job'进入项目spiders目录, 修改 spider py 文件(你自己的spider的主文件):def __init__(self):改为:def __init__(self, *args, **kwargs):最后不要忘了重新部署一...
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How do I get the number of elements in a list?

...objects with a "size" in Python, in particular, have an attribute called ob_size, where the number of elements in the object is cached. So checking the number of objects in a list is very fast. But if you're checking if list size is zero or not, don't use len - instead, put the list in a boolean co...
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Are nested try/except blocks in python a good programming practice?

...EAFP. Personally, I prefer to avoid nesting when it's not necessary: def __getattribute__(self, item): try: return object.__getattribute__(item) except AttributeError: pass # fallback to dict try: return self.dict[item] except KeyError: raise Attrib...
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Why aren't python nested functions called closures?

...variable from an enclosing scope that has finished its execution. def make_printer(msg): def printer(): print msg return printer printer = make_printer('Foo!') printer() When make_printer is called, a new frame is put on the stack with the compiled code for the printer function a...
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Limit file format when using ?

...ge behavior further (according to my tests), it will add different filters based on what you specify, but a) it's not bundled, so it will list each extension as a separate option and b) it will always add some in-build extensions such as .html, and c) as already stated, it will always pre-select (*)...
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How can I find script's directory with Python? [duplicate]

... You need to call os.path.realpath on __file__, so that when __file__ is a filename without the path you still get the dir path: import os print(os.path.dirname(os.path.realpath(__file__))) ...
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What is the id( ) function used for?

...d and user does not see them: class democlass: classvar = 24 def __init__(self, var): self.instancevar1 = var self.instancevar2 = 42 def whoreferencesmylocalvars(self, fromwhere): return {__l__: {__g__ for __g__ in fromwhere ...
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Viewing all defined variables [duplicate]

...r package outside of IPython too. Very useful! – Hugh_Kelley Jul 25 '19 at 7:50 add a comment  |  ...
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error C2780: \'void __cdecl std::sort(_RI,_RI,_Pr)\' : expects 3 argum...

error C2780: 'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 providedprog7.cpp(8) :error C2780:'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 provided C: Pr...prog7.cpp(8) : error C2780: 'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 provided C:...