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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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Android: How to bind spinner to custom object list?
...t. global variables or code in 1 very, very long file are working too you know... Btw you should comment on old threads because they still appear in todays searches and ppl will use those (todays) wrong answers.
– Srneczek
Jan 12 '16 at 9:41
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What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how
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@LIttleAncientForestKami verified with 3.7.0, by now the values are set as constants DEFAULT_SOURCE and DEFAULT_TARGET, but still both set to 1.5.
– Adam Burley
Dec 17 '17 at 12:40
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When to use ' (or quote) in Lisp?
...et (+ 3 2), + is then invoked on 3 and 2 yielding 5. Our original form is now (* 5 3) yielding 15.
Explain quote Already!
Alright. As seen above, all arguments to a function are evaluated, so if you would like to pass the symbol a and not its value, you don't want to evaluate it. Lisp symbols ca...
What is the difference between “git init” and “git init --bare”?
...u don't get a directory where you can work. Everything in the directory is now what was contained in the .git folder in the above case.
Why You Would Use One vs. the Other
The need for git repos without a working directory is the fact that you can push branches to it and it doesn't manage what som...
How to upgrade PostgreSQL from version 9.6 to version 10.1 without losing data?
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Minor update: brew now also has the option to use brew services stop postgresql and brew services start postgresql instead of directly calling launchctl unload and launchctl load.
– florish
Mar 1 '17 at 15...
How to modify a pull request on GitHub to change target branch to merge into?
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You can now:
https://github.com/blog/2224-change-the-base-branch-of-a-pull-request
"You can now change the base branch of an open pull request. After you’ve created a pull request, you can modify the base branch so that the change...
How to remove constraints from my MySQL table?
...column to other tables columns. Mine had a standard name given to it. Also now I now that you can drop foreign keys safetely without the column itself being dropped
– Lealo
Aug 18 '17 at 0:35
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Multiple inheritance/prototypes in JavaScript
...Update (2019): The original post is getting pretty outdated. This article (now internet archive link, since domain went away) and its associated GitHub library are a good modern approach.
Original post:
Multiple inheritance [edit, not proper inheritance of type, but of properties; mixins] in Javasc...
Best practices for copying files with Maven
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Is the task descriptor now deprecated?
– Matt
Apr 19 '11 at 17:00
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