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How to pull a random record using Django's ORM?
...['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
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How to print a percentage value in python?
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Is float(1) really more pythonic than 1.?
– Tobias Kienzler
Jul 17 '13 at 7:58
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What is a regular expression for a MAC Address?
...at" comes from Wikipedia, not the 802.3 standards body. IEEE 802-2014 actually specifies hyphens for ordinary MAC addresses (§ 8.1 ¶ 3) and colons for the obsolescent bit-reversed notation (¶ 4). Importantly, in practice, no one observes this. We simply use one or the other, but never mix them...
Django rest framework nested self-referential objects
... the `subcategories` field
return CategorySerializer()
Actually, as you've noted the above isn't quite right.
This is a bit of a hack, but you might try adding the field in after the serializer is already declared.
class CategorySerializer(serializers.ModelSerializer):
parentCat...
setup.py examples?
...through Python packages on the Python Package Index. Just download the tarball, unpack it, and have a look at the setup.py file. Or even better, only bother looking through packages that list a public source code repository such as one hosted on GitHub or BitBucket. You're bound to run into one on t...
IllegalArgumentException or NullPointerException for a null parameter? [closed]
... one of those things that you should do whatever you prefer and both are really correct?
26 Answers
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NULL values inside NOT IN clause
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@Ian - It looks like "A NOT IN ( 'X', 'Y' )" actually is an alias for A <> 'X' AND A <> 'Y' in SQL. (I see that you discovered this yourself in stackoverflow.com/questions/3924694/…, but wanted to make sure your objection was addressed in this question.)
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Environment variable to control java.io.tmpdir?
...s.
On Windows, OpenJDK's get_temp_directory() function makes a Win32 API call to GetTempPath(); this is how on Windows, Java reflects the value of the TMP environment variable.
On Linux and Solaris, the same get_temp_directory() functions return a static value of /tmp/.
I don't know if the actual...
SQLite in Android How to update a specific row
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It's actually a walk-around. The Third param of db.update() should be the where clause only, and the fourth is the actual condition values. In this case, the line should be: myDB.update(TableName, cv, "_id=?", new String[]{id}). SQLit...
What is the rationale for all comparisons returning false for IEEE754 NaN values?
Why do comparisons of NaN values behave differently from all other values?
That is, all comparisons with the operators ==, =, where one or both values is NaN returns false, contrary to the behaviour of all other values.
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