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Get class name of django model
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Django models are derived from the ModelBase, which is the Metaclass for all models.
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What does the caret operator (^) in Python do?
...his way:
1000 # 8 (binary)
0011 # 3 (binary)
---- # APPLY XOR ('vertically')
1011 # result = 11 (binary)
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How do I check if the Java JDK is installed on Mac?
How do you check if Java SDK is installed on a Mac?
8 Answers
8
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What is the canonical way to check for errors using the CUDA runtime API?
...ag wiki , I see it is often suggested that the return status of every API call should checked for errors. The API documentation contains functions like cudaGetLastError , cudaPeekAtLastError , and cudaGetErrorString , but what is the best way to put these together to reliably catch and report err...
relative path in require_once doesn't work
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Note that you should manually include the trailing slash in after __DIR__. So: require_once(__DIR__.'/../class/user.php'); Per the documentation, the trailing slash is omitted except for the root directory.
– Ariel Allon
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What is the use of static variable in C#? When to use it? Why can't I declare the static variable in
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A static variable shares the value of it among all instances of the class.
Example without declaring it static:
public class Variable
{
public int i = 5;
public void test()
{
i = i + 5;
Console.WriteLine(i);
}
}
public class Exercise
{
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Is it intended by the C++ standards committee that in C++11 unordered_map destroys what it inserts?
... always move from its argument. It's supposed to move if the argument is really an rvalue, and copy if it's an lvalue.
The behaviour, you observe, which always moves, is a bug in libstdc++, which is now fixed according to a comment on the question. For those curious, I took a look at the g++-4.8 he...
Update MongoDB field using value of another field
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The best way to do this is in version 4.2+ which allows using of aggregation pipeline in the update document and the updateOne, updateMany or update collection method. Note that the latter has been deprecated in most if not all languages drivers.
MongoDB 4.2+
Version 4.2 ...
What's the difference between dist-packages and site-packages?
I'm a bit miffed by the python package installation process. Specifically, what's the difference between packages installed in the dist-packages directory and the site-packages directory?
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Python Sets vs Lists
...move the object creation now. The setup phase of the timeit loops is only called once (docs.python.org/2/library/timeit.html#timeit.Timer.timeit).
– Ellis Percival
Sep 30 '14 at 10:09
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