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Django: Get an object form the DB, or 'None' if nothing matches
... = models.CharField(max_length=255)
objects = GetOrNoneManager()
And now I can do this:
bob_or_none = Person.objects.get_or_none(name='Bob')
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What exactly are iterator, iterable, and iteration?
... @jlh why would __len__ be necessarily tied to iteration? How would knowing the length of something help you iterate over it?
– shadowtalker
Sep 19 '18 at 6:45
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How can I check if a value is a json object?
...a value which is a json object on success and a string 'false' on failure. Now how can I check whether the returned value is a json object?
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How to “re-run with -deprecation for details” in sbt?
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As times flows new solutions are emerged. So, now you could re-run the scala compiler without issuing entire project rebuild.
You need to install ensime-sbt plugin:
addSbtPlugin("org.ensime" % "sbt-ensime" % "1.0.0")
After that you could use the ensimeCompileOnly ta...
View not attached to window manager crash
... the Async task, the async task runs in the background. that is desirable. Now, this Async task has a progress dialog which is attached to the Activity, if you ask how to see the code:
pDialog = new ProgressDialog(CLASS.this);
You are passing the Class.this as context to the argument. So the Prog...
How to grep Git commit diffs or contents for a certain word?
... Use some made-up, non-regexy words instead.
The git diff documentation now includes:
To illustrate the difference between -S<regex> --pickaxe-regex and
-G<regex>, consider a commit with the following diff in the same
file:
+ return frotz(nitfol, two->ptr, 1, 0);
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- ...
How to test an Internet connection with bash?
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Careful now!" cat /sys/class/net/wwan0/carrier does not work on ubuntu 14.04 LTS.
– dotnetCarpenter
Mar 1 '15 at 20:45
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Max length for client ip address [duplicate]
... a database column storing client ip addresses? I have it set to 16 right now, but could I get an ip address that is longer than that with IPv6, etc?
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Pretty-print an entire Pandas Series / DataFrame
...n printed. If the above answer did not work for previous versions, it does now.
– H Froedge
Sep 28 '18 at 7:02
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Disposing WPF User Controls
...I was hoping there would be a cleaner way than this, but it looks like for now this is the best to do it.
– Mark Heath
Sep 4 '09 at 6:41
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