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MIN and MAX in C

...afety bonus too) in a GCC statement expression: #define max(a,b) \ ({ __typeof__ (a) _a = (a); \ __typeof__ (b) _b = (b); \ _a > _b ? _a : _b; }) Everyone says "oh I know about double evaluation, it's no problem" and a few months down the road, you'll be debugging the silliest ...
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What does “hashable” mean in Python?

...if it has a hash value which never changes during its lifetime (it needs a __hash__() method), and can be compared to other objects (it needs an __eq__() or __cmp__() method). Hashable objects which compare equal must have the same hash value. Hashability makes an object usable as a dictionary ...
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Why do we use __init__ in Python classes?

...ical piece of understanding: the difference between a class and an object. __init__ doesn't initialize a class, it initializes an instance of a class or an object. Each dog has colour, but dogs as a class don't. Each dog has four or fewer feet, but the class of dogs doesn't. The class is a concept o...
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Difference between abstract class and interface in Python

... NotImplementedError("Class %s doesn't implement aMethod()" % (self.__class__.__name__)) is more informative error message :) – naught101 Sep 3 '14 at 1:43 9 ...
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Python constructors and __init__

...ame but different arguments. In your code example, you're not overloading __init__(). What happens is that the second definition rebinds the name __init__ to the new method, rendering the first method inaccessible. As to your general question about constructors, Wikipedia is a good starting point....
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Finding the source code for built-in Python functions?

... particular module or function is implemented in you can usually print the __file__ attribute. Alternatively, you may use the inspect module, see the section Retrieving Source Code in the documentation of inspect. For built-in classes and methods this is not so straightforward since inspect.getfile...
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What is a Python equivalent of PHP's var_dump()? [duplicate]

When debugging in PHP, I frequently find it useful to simply stick a var_dump() in my code to show me what a variable is, what its value is, and the same for anything that it contains. ...
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Python - Get path of root project structure

...tils.py In definitions.py you can define (this requires import os): ROOT_DIR = os.path.dirname(os.path.abspath(__file__)) # This is your Project Root Thus, with the Project Root known, you can create a variable that points to the location of the configuration (this can be defined anywhere, but ...
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Why is Python running my module when I import it, and how do I stop it?

...is: # stuff to run always here such as class/def def main(): pass if __name__ == "__main__": # stuff only to run when not called via 'import' here main() See What is if __name__ == "__main__" for? It does require source control over the module being imported, however. Happy coding. ...
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What does Python's eval() do?

... command string and then have python run it as code. So for example: eval("__import__('os').remove('file')"). – BYS2 Feb 21 '12 at 19:24 ...