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Filtering for empty or NULL names in a queryset
...lias (optional) which I need to search for. So, I need a query to give me all the names that have an alias set.
7 Answers
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How do I check if there are duplicates in a flat list?
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Use set() to remove duplicates if all values are hashable:
>>> your_list = ['one', 'two', 'one']
>>> len(your_list) != len(set(your_list))
True
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What is the difference between a mutable and immutable string in C#?
...pe
To "effect a change" on a string represented as a C# String, you actually create a new String object. The original String is not changed ... because it is unchangeable.
In most cases it is better to use String because it is easier reason about them; e.g. you don't need to consider the possib...
How does __proto__ differ from constructor.prototype?
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I've been trying to wrap my head around this recently and finally came up with this "map" that I think sheds full light over the matter
http://i.stack.imgur.com/KFzI3.png
I know I'm not the first one making this up but it was more interesting figuring it out that finding it :-). An...
Check if a class has a member function of a given signature
...oid ReportMemUsage(const TMap& m, std::true_type)
{
// We may call used_memory() on m here.
}
template<typename TMap>
void ReportMemUsage(const TMap&, std::false_type)
{
}
template<typename TMap>
void ReportMemUsage(const TMap& m)
{
ReportMemUsage(m,
std:...
Which iomanip manipulators are 'sticky'?
... the comments below:
By Martin:
@Chareles: Then by this requirement all manipulators are sticky. Except setw which seems to be reset after use.
By Charles:
Exactly! and the only reason that setw appears to behave differently is because there are requirements on formatted output operat...
Error “can't use subversion command line client : svn” when opening android project checked out from
...svn command because it's not on PATH, and it doesn't know where svn is installed.
One way to fix is to edit the PATH environment variable: add the directory that contains svn.exe. You will need to restart Android Studio to make it re-read the PATH variable.
Another way is to set the absolute path ...
Difference between String replace() and replaceAll()
What's the difference between java.lang.String 's replace() and replaceAll() methods,
other than later uses regex? For simple substitutions like, replace . with / ,
is there any difference?
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Converting between datetime, Timestamp and datetime64
...>> numpy.__version__
'1.6.2' # current version available via pip install numpy
I can reproduce the long value on numpy-1.8.0 installed as:
pip install git+https://github.com/numpy/numpy.git#egg=numpy-dev
The same example:
>>> from datetime import datetime
>>> import num...
What to put in a python module docstring? [closed]
...ngs; the module's own docstring should describe them very summarily (if at all) and rather concentrate on a concise summary of what the module as a whole can do for you, ideally with some doctested examples (just like functions and classes ideally should have doctested examples in their docstrings)....