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Rename all files in directory from $filename_h to $filename_half?

... Just use bash, no need to call external commands. for file in *_h.png do mv "$file" "${file/_h.png/_half.png}" done Do not add #!/bin/sh For those that need that one-liner: for file in *.png; do mv "$file" "${file/_h.png/_half.png}"; done ...
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How to implement __iter__(self) for a container object (Python)

... I normally would use a generator function. Each time you use a yield statement, it will add an item to the sequence. The following will create an iterator that yields five, and then every item in some_list. def __iter__(self): ...
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Why is “if not someobj:” better than “if someobj == None:” in Python?

...a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero. Otherwise, if the object has a __len__ special method (as do container built-ins, li...
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Chaining multiple filter() in Django, is this a bug?

I always assumed that chaining multiple filter() calls in Django was always the same as collecting them in a single call. 4...
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Format date and time in a Windows batch script

... All this can be done in just 2 lines using ordinary string replacement: stackoverflow.com/a/23558738/1879699 – Andreas Apr 22 '16 at 9:34 ...
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Why does ReSharper tell me “implicitly captured closure”?

... use. The compiler generates a class for both lambda expressions and puts all variables in that class which are used in the lambda expressions. So in my example g and i are held in the same class for execution of my delegates. If g is a heavy object with a lot of resources left behind, the garbage...
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The tilde operator in Python

...a unary operator (taking a single argument) that is borrowed from C, where all data types are just different ways of interpreting bytes. It is the "invert" or "complement" operation, in which all the bits of the input data are reversed. In Python, for integers, the bits of the twos-complement repr...
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How to avoid having class data shared among instances?

...problem you face is that x.list and y.list are the same list, so when you call append on one, it affects the other. – Matt Moriarity Nov 5 '09 at 14:04 ...
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Determining 32 vs 64 bit in C++

...esentation. I prefer ENVIRONMENT64 / ENVIRONMENT32. Then I find out what all of the major compilers use for determining if it's a 64 bit environment or not and use that to set my variables. // Check windows #if _WIN32 || _WIN64 #if _WIN64 #define ENVIRONMENT64 #else #define ENVIRONMENT32 #endif...
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How to print to console in pytest?

... Using -s option will print output of all functions, which may be too much. If you need particular output, the doc page you mentioned offers few suggestions: Insert assert False, "dumb assert to make PyTest print my stuff" at the end of your function, and you...