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Correct way to use get_or_create?
...f the fields have to be included in defaults. In case CREATE event occurs, all the fields are taken into consideration.
It looks like you need to be returning into a tuple, instead of a single variable, do like this:
customer.source,created = Source.objects.get_or_create(name="Website")
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is not JSON serializable
...fe tage. stackoverflow.com/a/57939897/4157431
– Rami Alloush
Sep 14 '19 at 23:01
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How do I cast a variable in Scala?
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The preferred technique is to use pattern matching. This allows you to gracefully handle the case that the value in question is not of the given type:
g match {
case g2: Graphics2D => g2
case _ => throw new ClassCastException
}
This block replicates the semantics of th...
Read a text file using Node.js?
...e.log(data)
});
To break that down a little for you process.argv will usually have length two, the zeroth item being the "node" interpreter and the first being the script that node is currently running, items after that were passed on the command line. Once you've pulled a filename from argv then...
Removing a list of characters in string
...unicodes), the absolutely best method is str.translate:
>>> chars_to_remove = ['.', '!', '?']
>>> subj = 'A.B!C?'
>>> subj.translate(None, ''.join(chars_to_remove))
'ABC'
Otherwise, there are following options to consider:
A. Iterate the subject char by char, omit unwa...
pip issue installing almost any library
I have a difficult time using pip to install almost anything. I'm new to coding, so I thought maybe this is something I've been doing wrong and have opted out to easy_install to get most of what I needed done, which has generally worked. However, now I'm trying to download the nltk library, and neit...
How to check for valid email address? [duplicate]
...ere is no point. Even if you can verify that the email address is syntactically valid, you'll still need to check that it was not mistyped, and that it actually goes to the person you think it does. The only way to do that is to send them an email and have them click a link to verify.
Therefore, a ...
Getting the index of the returned max or min item using max()/min() on a list
... values = [3,6,1,5], and need the index of the smallest element, i.e. index_min = 2 in this case.
Avoid the solution with itemgetter() presented in the other answers, and use instead
index_min = min(range(len(values)), key=values.__getitem__)
because it doesn't require to import operator nor to ...
Android selector & text color
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Should the selector really reside under res/color folder?
– mr5
Apr 21 '17 at 4:29
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Finding the type of an object in C++
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dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime...