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Redirect stdout to a file in Python?
...t it back when you're done, sys.stdout = stdout. That way if you're being called from a function that uses print you don't screw them up.
– mgold
Dec 20 '12 at 15:06
4
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Determine if variable is defined in Python [duplicate]
...ime? This is not always obvious because (1) the variable could be conditionally set, and (2) the variable could be conditionally deleted. I'm looking for something like defined() in Perl or isset() in PHP or defined? in Ruby.
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Referring to the null object in Python
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SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
django urls without a trailing slash do not redirect
...ost.". "The APPEND_SLASH setting is only used if CommonMiddleware is installed...". I prefer Michael Gendin's answer for a cleaner solution.
– Wtower
Feb 11 '15 at 9:26
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String concatenation: concat() vs “+” operator
...then throwing it away when you create the final String. In practice memory allocation is surprisingly fast.
Update: As Pawel Adamski notes, performance has changed in more recent HotSpot. javac still produces exactly the same code, but the bytecode compiler cheats. Simple testing entirely fails bec...
Timeout on a function call
I'm calling a function in Python which I know may stall and force me to restart the script.
18 Answers
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How to use timeit module
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The way timeit works is to run setup code once and then make repeated calls to a series of statements. So, if you want to test sorting, some care is required so that one pass at an in-place sort doesn't affect the next pass with already sorted data (that, of course, would make the Timsort reall...
Why would one use nested classes in C++?
... it at any time so you can not use it.
Look at std::list or std::map they all contain hidden classes (or do they?). The point is they may or may not, but because the implementation is private and hidden the builders of the STL were able to update the code without affecting how you used the code, or...
A proper wrapper for console.log with correct line number?
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This is an old question and All the answers provided are overly hackey, have MAJOR cross browser issues, and don't provide anything super useful. This solution works in every browser and reports all console data exactly as it should. No hacks required...
What is a mixin, and why are they useful?
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Probably not an issue in this example, but you generally want to put the main base class as the last element within the parenthesis so to create the inheritance chain: Request==>Mixin==>...==>BaseRequest. See here: ianlewis.org/en/mixins-and-python
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