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Fastest way to get the first object from a queryset in django?
...eturn None if there aren't any. There are lots of ways to do this which all work. But I'm wondering which is the most performant.
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How can I open multiple files using “with open” in Python?
I want to change a couple of files at one time, iff I can write to all of them. I'm wondering if I somehow can combine the multiple open calls with the with statement:
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Is it possible to declare two variables of different types in a for loop?
...and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above will give you:
int i set to 1
double f set to 1.0
std::string s set to "...
Constructor overload in TypeScript
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TypeScript allows you to declare overloads but you can only have one implementation and that implementation must have a signature that is compatible with all overloads. In your example, this can easily be done with an optional parameter...
What is getattr() exactly and how do I use it?
... understand about getattr() is that getattr(li, "pop") is the same as calling li.pop .
14 Answers
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How many concurrent AJAX (XmlHttpRequest) requests are allowed in popular browsers?
... No, the limits are imposed on the domain. So you could technically get FF up to 12 connections if you had a subdomain in addition to your site.
– Bob
Feb 18 '09 at 13:39
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How to implement an ordered, default dict? [duplicate]
...deredDict() and defaultdict() from collections in one object, which shall be an ordered, default dict .
Is this possible?
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How can I get a list of all classes within current module in Python?
I've seen plenty of examples of people extracting all of the classes from a module, usually something like:
11 Answers
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How to avoid explicit 'self' in Python?
...s leads to useful properties, such as: you can't add members which accidentally shadow non-members and thereby break code.
One extreme example: you can write a class without any knowledge of what base classes it might have, and always know whether you are accessing a member or not:
class A(some_fu...
How to import multiple .csv files at once?
...ariables but each from different times.
Is there a way in R to import them all simultaneously rather than having to import them all individually?
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