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How to import the class within the same directory or sub directory?
...
Python 2
Make an empty file called __init__.py in the same directory as the files. That will signify to Python that it's "ok to import from this directory".
Then just do...
from user import User
from dir import Dir
The same holds true if the files are in a...
How do I filter query objects by date range in Django?
...
Use
Sample.objects.filter(date__range=["2011-01-01", "2011-01-31"])
Or if you are just trying to filter month wise:
Sample.objects.filter(date__year='2011',
date__month='01')
Edit
As Bernhard Vallant said, if you want a query...
What is the meaning of single and double underscore before an object name?
...owever, nothing special is done with the name itself.
To quote PEP-8:
_single_leading_underscore: weak "internal use" indicator. E.g. from M import * does not import objects whose name starts with an underscore.
Double Underscore (Name Mangling)
From the Python docs:
Any identifier of th...
Can I zip more than two lists together in Scala?
...neLists[A](ss:List[A]*) = {
val sa = ss.reverse;
(sa.head.map(List(_)) /: sa.tail)(_.zip(_).map(p=>p._2 :: p._1))
}
For example:
combineLists(List(1, 2, 3), List(10,20), List(100, 200, 300))
// => List[List[Int]] = List(List(1, 10, 100), List(2, 20, 200))
The answer is truncated t...
Proper way to declare custom exceptions in modern Python?
... (or pass extra args), do this:
class ValidationError(Exception):
def __init__(self, message, errors):
# Call the base class constructor with the parameters it needs
super(ValidationError, self).__init__(message)
# Now for your custom code...
self.errors = erro...
Using mixins vs components for code reuse in Facebook React
...nding fields.
Source (gist)
define(function () {
'use strict';
var _ = require('underscore');
var ValidationMixin = {
getInitialState: function () {
return {
errors: []
};
},
componentWillMount: function () {
this.assertValidatorsDefined();
},
...
How to step through Python code to help debug issues?
...rSummoner, pudb is great for that. Also pydev
– alpha_989
Jun 11 '18 at 19:45
pdb is not a command line tool. To use i...
How can I create directory tree in C++/Linux?
...he standard header <filesystem> with
function
std::filesystem::create_directories
which should be used in modern C++ programs.
The C++ standard functions do not have the POSIX-specific explicit
permissions (mode) argument, though.
However, here's a C function that can be compiled with C++ com...
Why declare unicode by string in python?
...racters in the string (that is, u'\u2665' is now legal). You can use from __future__ import unicode_literals to make it the default.
This only applies to Python 2; in Python 3 the default is Unicode, and you need to specify a b in front (like b'These are bytes', to declare a sequence of bytes).
...
Loop backwards using indices in Python?
...as no way to tell the xrange to go backwards... (Since Python 2.6 it calls __reversed__().)
– Robert Siemer
Jun 21 '12 at 18:31
...