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How to invoke the super constructor in Python?
...on-3.x the process has been simplified:
Python-2.x
class A(object):
def __init__(self):
print "world"
class B(A):
def __init__(self):
print "hello"
super(B, self).__init__()
Python-3.x
class A(object):
def __init__(self):
print("world")
class B(A):
def __init__(self):
print...
In which case do you use the JPA @JoinTable annotation?
...ble named Task and add a foreign key column to the task table named project_id:
Project Task
------- ----
id id
name name
project_id
This way, it will be possible to determine the project for each row in the task table. If you use this approach, in your e...
Solving “Who owns the Zebra” programmatically?
...all drink different drinks.
# They all smoke different cigarettes.
for vars_ in (colors, nationalities, pets, drinks, cigarettes):
problem.addConstraint(AllDifferentConstraint(), vars_)
# In the middle house they drink milk.
#NOTE: interpret "middle" in a numerical sense (not geometrical)
probl...
Python multiprocessing pool.map for multiple arguments
... function:
import multiprocessing
from itertools import product
def merge_names(a, b):
return '{} & {}'.format(a, b)
if __name__ == '__main__':
names = ['Brown', 'Wilson', 'Bartlett', 'Rivera', 'Molloy', 'Opie']
with multiprocessing.Pool(processes=3) as pool:
results = poo...
Django “xxxxxx Object” display customization in admin action sidebar
...
__unicode__ does do that. Your model should look something like this:
class SomeModel(models.Model):
def __unicode__(self):
return 'Policy: ' + self.name
On Python 3 you need to use __str__:
def __str__(self):
...
C++ mark as deprecated
...his all I got was a Microsoft specific solution; #pragma deprecated and __declspec(deprecated) .
7 Answers
...
How to override the [] operator in Python?
...
You need to use the __getitem__ method.
class MyClass:
def __getitem__(self, key):
return key * 2
myobj = MyClass()
myobj[3] #Output: 6
And if you're going to be setting values you'll need to implement the __setitem__ method too,...
How do I write good/correct package __init__.py files
...
__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 n...
Class method differences in Python: bound, unbound and static
... and unbound methods.
Basically, a call to a member function (like method_one), a bound function
a_test.method_one()
is translated to
Test.method_one(a_test)
i.e. a call to an unbound method. Because of that, a call to your version of method_two will fail with a TypeError
>>> a_tes...
__getattr__ on a module
How can implement the equivalent of a __getattr__ on a class, on a module?
8 Answers
...