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Explaining Python's '__enter__' and '__exit__'

... Using these magic methods (__enter__, __exit__) allows you to implement objects which can be used easily with the with statement. The idea is that it makes it easy to build code which needs some 'cleandown' code executed (think of it as a try-finally block). Some more ex...
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How do I get Pyflakes to ignore a statement?

... # noqa only ignores certain warnings/errors, but not all -- in order to deal with this, a workaround involves installing/using the package at pypi.python.org/pypi/flake8-respect-noqa – Mark Jan 18 '16 at 0:15 ...
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?

... gcc-4.8 1.53s 1.52s -Os In some cases you can alleviate the effect of disadvantageous optimizations by asking gcc to optimize for your particular processor (using options -mtune=native or -march=native): Processor Compiler Time (-O2 -mtune=native) Time (-Os...
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How do I execute a string containing Python code in Python?

...;>> x 4 However, the first step should be to ask yourself if you really need to. Executing code should generally be the position of last resort: It's slow, ugly and dangerous if it can contain user-entered code. You should always look at alternatives first, such as higher order functions, ...
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Get a filtered list of files in a directory

...t a list of files in a directory using Python, but I do not want a list of ALL the files. 14 Answers ...
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How can I make a time delay in Python? [duplicate]

...print less frequently than that, because it takes time to print and handle all the buffers that entails (possibly doing a kernel context switch), and to register the alarm signal, but... yeah. A little under once per minute. – Parthian Shot Jun 17 '15 at 19:29 ...
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Why are all fields in an interface implicitly static and final?

I am just trying to understand why all fields defined in an Interface are implicitly static and final . The idea of keeping fields static makes sense to me as you can't have objects of an interface but why they are final (implicitly)? ...
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Getting Django admin url for an object

...e was an easy way to get the admin url of an object, and I had written a small filter that I'd use like this: <a href="{{ object|admin_url }}" .... > ... </a> ...
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What is the purpose of the single underscore “_” variable in Python?

...cate that part of a function result is being deliberately ignored (Conceptually, it is being discarded.), as in code like: label, has_label, _ = text.partition(':'). As part of a function definition (using either def or lambda), where the signature is fixed (e.g. by a callback or parent class API), ...
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Or versus OrElse

...oth terms. When temp Is DBNull.Value, it can't be compared to zero, so it falls over. You should use... well, whichever one makes sense. share | improve this answer | follow...