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How do I override __getattr__ in Python without breaking the default behavior?
...ill be called first (only works for new style classes i.e. those that inherit from object). In this case, you can preserve default behaviour like so:
class Foo(object):
def __getattribute__(self, name):
if some_predicate(name):
# ...
else:
# Default behav...
Can't pickle when using multiprocessing Pool.map()
...function to divide out work simultaneously. When I use the following code, it works fine:
12 Answers
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What are “named tuples” in Python?
...although there is a recipe for implementation in Python 2.4.
For example, it is common to represent a point as a tuple (x, y). This leads to code like the following:
pt1 = (1.0, 5.0)
pt2 = (2.5, 1.5)
from math import sqrt
line_length = sqrt((pt1[0]-pt2[0])**2 + (pt1[1]-pt2[1])**2)
Using a name...
Multiple levels of 'collection.defaultdict' in Python
Thanks to some great folks on SO, I discovered the possibilities offered by collections.defaultdict , notably in readability and speed. I have put them to use with success.
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Does python have an equivalent to Java Class.forName()?
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Reflection in python is a lot easier and far more flexible than it is in Java.
I recommend reading this tutorial
There's no direct function (that I know of) which takes a fully qualified class name and returns the class, however you have all the pieces needed to build that, and you can ...
Are PHP include paths relative to the file or the calling code?
...tion to the location of B.PHP, or to the location of A.PHP? That is, does it matter which file the include is called from, or only what the current working directory is- and what determines the current working directory?
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How do I write good/correct package __init__.py files
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__all__ is very good - it helps guide import statements without automatically importing modules
http://docs.python.org/tutorial/modules.html#importing-from-a-package
using __all__ and import * is redundant, only __all__ is needed
I think one of t...
What is a mixin, and why are they useful?
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A mixin is a special kind of multiple inheritance. There are two main situations where mixins are used:
You want to provide a lot of optional features for a class.
You want to use one particular feature in a lot of different classes.
For an example of number one,...
PHP function overloading
...names and do not include argument lists, so you cannot have two functions with the same name. Class method overloading is different in PHP than in many other languages. PHP uses the same word but it describes a different pattern.
You can, however, declare a variadic function that takes in a variabl...
How to make a cross-module variable?
The __debug__ variable is handy in part because it affects every module. If I want to create another variable that works the same way, how would I do it?
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