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How do I get the object if it exists, or None if it does not exist?
...u can do it this way:
go = Content.objects.filter(name="baby").first()
Now go variable could be either the object you want or None
Ref: https://docs.djangoproject.com/en/1.8/ref/models/querysets/#django.db.models.query.QuerySet.first
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Python 3 ImportError: No module named 'ConfigParser'
... A moving target on this one but I use pip3 install mysql-connector. Now available from MySQL for python3 support. release at time of typing is 2.1.3.
– Longmang
Jun 7 '16 at 9:42
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Reloading submodules in IPython
...ole. Unfortunately I am not very happy with workflow that I am using right now, I would appreciate some advice.
13 Answers
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Getting a list of associative array keys
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I'm switching this to the accepted answer now. Only IE8 doesn't support it anymore (for which a polyfill is available developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…)
– Simon_Weaver
Dec 11 '17 at 1:55
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How to select multiple files with ?
...s not user friendly, the avarage user doesn't understand it, doesn't even know what a "ctrl button" does, and it cannot select files in different folders.
– Jean-Paul
Jan 30 '17 at 16:04
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What does FETCH_HEAD in Git mean?
...is a tag for a version of the software. To my surprise, release_1 was then nowhere to be found on my local machine. I had to type
git tag release_1 FETCH_HEAD
to complete the copy of the tagged chain of commits (release_1) from the remote repository to the local one. Fetch had found the remote ...
Plugin execution not covered by lifecycle configuration (JBossas 7 EAR archetype)
...ree with rapt. My POM has no dependency on m2e and I would want to add one now just because I happen to be using Eclipse as my IDE. That is an impost to others working on the same project that may well be using another IDE such as IntelliJ. If m2e needs these hints then it should be part of the m2e...
Why is f(i = -1, i = -1) undefined behavior?
...Then this:
f(i=-1, i=-1)
might become:
clear i
clear i
decr i
decr i
Now i is -2.
It is probably a bogus example, but it is possible.
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Most efficient way to create a zero filled JavaScript array?
...sional arrays and it seemed to greatly speed up my test cases. Having just now done some more testing on FF41 and Chrome45.0.2454.99 m. Yes, I guess I really needed more space to explain myself. Most of my testing was bias I will admit. But, check this out. Predefine a var and using just this line (...
What happens to C# Dictionary lookup if the key does not exist?
...corresponding value
}
else
{
// Key wasn't in dictionary; "value" is now 0
}
(Using ContainsKey and then the the indexer makes it look the key up twice, which is pretty pointless.)
Note that even if you were using reference types, checking for null wouldn't work - the indexer for Dictionary...