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Python Sets vs Lists
... as lists, except for their immutability.
Iterating
>>> def iter_test(iterable):
... for i in iterable:
... pass
...
>>> from timeit import timeit
>>> timeit(
... "iter_test(iterable)",
... setup="from __main__ import iter_test; iterable = set(range(1...
Serializing class instance to JSON
...N for your class.
A simple solution would be to call json.dumps() on the .__dict__ member of that instance. That is a standard Python dict and if your class is simple it will be JSON serializable.
class Foo(object):
def __init__(self):
self.x = 1
self.y = 2
foo = Foo()
s = js...
How to spread django unit tests over multiple files?
...er valid from Django 1.6, see this post.
You can create tests folder with ___init___.py inside (so that it becomes a package). Then you add your split test .py files there and import all of them in ___init___.py.
I.e: Substitute the test.py file with a module that looks and acts like the file:
Cr...
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...
Multi-line string with extra space (preserved indentation)
...o use a helper function and some variable substitution tricks:
unset text
_() { text="${text}${text+
}${*}"; }
# That's an empty line which demonstrates the reasoning behind
# the usage of "+" instead of ":+" in the variable substitution
# above.
_ ""
_ "this is line one"
_ "this is line two"
_ "...
How do I implement __getattribute__ without an infinite recursion error?
...n a class, but return all others normally. How do I accomplish this with __getattribute__ ?
6 Answers
...
How to implement a good __hash__ function in python [duplicate]
...
__hash__ should return the same value for objects that are equal. It also shouldn't change over the lifetime of the object; generally you only implement it for immutable objects.
A trivial implementation would be to just ret...
Python integer division yields float
... -, * and / to special functions, such that e.g. a + b is equivalent to
a.__add__(b)
Regarding division in Python 2, there is by default only / which maps to __div__ and the result is dependent on the input types (e.g. int, float).
Python 2.2 introduced the __future__ feature division, which cha...
What is the purpose of the single underscore “_” variable in Python?
What is the meaning of _ after for in this code?
5 Answers
5
...
What is the difference between public, protected, package-private and private in Java?
...
The official tutorial may be of some use to you.
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| │ Class │ Package │ Subclass │ Subclass │ World |
| │ │ │(same pkg)│(diff pkg)│ |
|─────...
