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How to decorate a class?
...2.5, is there a way to create a decorator that decorates a class? Specifically, I want to use a decorator to add a member to a class and change the constructor to take a value for that member.
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Format date and time in a Windows batch script
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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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What is the __del__ method, How to call it?
...is used, probably not like that: obj1.del() . So, my questions is how to call the __del__ method?
5 Answers
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What does if __name__ == “__main__”: do?
...ngs:
it sets a few special variables like __name__, and then
it executes all of the code found in the file.
Let's see how this works and how it relates to your question about the __name__ checks we always see in Python scripts.
Code Sample
Let's use a slightly different code sample to explore ho...
What is __pycache__?
...'s files, respectively.
As a programmer, you can largely just ignore it... All it does is make your program start a little faster. When your scripts change, they will be recompiled, and if you delete the files or the whole folder and run your program again, they will reappear (unless you specificall...
CMake: Print out all accessible variables in a script
I'm wondering if there is a way to print out all accessible variables in CMake. I'm not interested in the CMake variables - as in the --help-variables option. I'm talking about my variables that I defined, or the variables defined by included scripts.
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Define a lambda expression that raises an Exception
...ur goal is to avoid a def, this obviously doesn't cut it. It does, however allow you to conditionally raise exceptions, e.g.:
y = lambda x: 2*x if x < 10 else raise_(Exception('foobar'))
Alternatively you can raise an exception without defining a named function. All you need is a strong stom...
Asking the user for input until they give a valid response
...logic.
while True:
data = input("Please enter a loud message (must be all caps): ")
if not data.isupper():
print("Sorry, your response was not loud enough.")
continue
else:
#we're happy with the value given.
#we're ready to exit the loop.
break
w...
Is it valid to replace http:// with // in a ?
... we test our sites in Firefox, Safari, IE6, IE7 and Opera. These browsers all understand that URL format.
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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...