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Does Python have “private” variables in classes?

... want to emulate private variables for some reason, you can always use the __ prefix from PEP 8. Python mangles the names of variables like __foo so that they're not easily visible to code outside the class that contains them (although you can get around it if you're determined enough, just like you...
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How to convert list of tuples to multiple lists?

... xs, ys = [x for x, y in zs], [y for x, y in zs] return xs, ys if __name__ == '__main__': from timeit import timeit setup_string='''\ N = 2000000 xs = list(range(1, N)) ys = list(range(N+1, N*2)) zs = list(zip(xs, ys)) from __main__ import t1, t2, t3 ''' print(f'zip:\t\t{timeit(...
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Aren't Python strings immutable? Then why does a + “ ” + b work?

... Consider: >>> a='asdf' >>> a.__repr__ <method-wrapper '__repr__' of str object at 0x1091aab90> >>> a='asdf' >>> a.__repr__ <method-wrapper '__repr__' of str object at 0x1091aab90> >>> a='qwer' >>> a.__repr_...
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What is getattr() exactly and how do I use it?

...answered Apr 10 '19 at 9:42 blue_noteblue_note 21k55 gold badges3737 silver badges6262 bronze badges ...
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Real world example about how to use property feature in python?

...changing terms. Complex calculation hidden behind an attribute: class PDB_Calculator(object): ... @property def protein_folding_angle(self): # number crunching, remote server calls, etc # all results in an angle set in 'some_angle' # It could also reference a ca...
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One-liner to check whether an iterator yields at least one element?

...In case the iterator yields something false-ish you can write any(True for _ in iterator). share | improve this answer | follow | ...
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Can we define implicit conversions of enums in c#?

...rmined from reflection /// </summary> private string _name; /// <summary> /// The DescriptionAttribute, if any, linked to the declaring field /// </summary> private DescriptionAttribute _descriptionAttribute; /// <summary...
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Elegant way to invert a map in Scala

... Assuming values are unique, this works: (Map() ++ origMap.map(_.swap)) On Scala 2.8, however, it's easier: origMap.map(_.swap) Being able to do that is part of the reason why Scala 2.8 has a new collection library. ...
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Why can't I use a list as a dict key in python?

...le, it'll work correctly with classes that have a custom comparison method __eq__. But if you convert them to strings, everything is compared by its string representation. – Aran-Fey May 20 '18 at 12:50 ...
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GET URL parameter in PHP

... $_GET is not a function or language construct—it's just a variable (an array). Try: <?php echo $_GET['link']; In particular, it's a superglobal: a built-in variable that's populated by PHP and is available in all scope...