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How do I clone a Django model instance object and save it to the database?
...one
obj.save()
If you want auto-generated key, set the new key to None.
More on UPDATE/INSERT here.
Official docs on copying model instances: https://docs.djangoproject.com/en/2.2/topics/db/queries/#copying-model-instances
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What is the easiest way to remove the first character from a string?
....160000 0.000000 1.160000 ( 1.157882)
Updating to incorporate one more suggested answer:
require 'benchmark'
N = 1_000_000
class String
def eat!(how_many = 1)
self.replace self[how_many..-1]
end
def first(how_many = 1)
self[0...how_many]
end
def shift(how_many = 1)
...
Understanding the difference between Object.create() and new SomeFunction()
...hey all have OOP in common. In fact JS’s OOP philosophy is much cleaner, more elegant and more universal than the class-based approach. They just failed to implement it nicely too. (JavaScript 2 was supposed to solve all that, and would have been quite nice. WebAssembly made all of it moot. :)
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Eclipse IDE for Java - Full Dark Theme
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Why use apparently meaningless do-while and if-else statements in macros?
...(corge);
else
gralt();
This doesn't work if instead of f(X) you have a more complicated body of code that needs to go in its own block, say for example to declare local variables. In the most general case the solution is to use something like do ... while to cause the macro to be a single state...
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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@Raithlin, Many many more gotchas. In JavaScript: "000" != "00", "000" == null, "000" == false, "0x0" == false, array() == 0, false != null, array() != null, false == "0x0", false == "000". In PHP, it's opposite behavior: "000" == "00", "000" != ...
Concurrent.futures vs Multiprocessing in Python 3
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I wouldn't call concurrent.futures more "advanced" - it's a simpler interface that works very much the same regardless of whether you use multiple threads or multiple processes as the underlying parallelization gimmick.
So, like virtually all instances of "sim...
How to print without newline or space?
... function imported from __future__ in Python 2; it only works in Python 3, more specifically 3.3 and later. In earlier versions you'll still need to flush manually with a call to sys.stdout.flush(). You'll also have to rewrite all other print statements in the file where you do this import.
Or you ...
Strip HTML from strings in Python
... Two years+ later, facing the same issue, and this is a far more elegant solution. Only change I made was to return self.fed as a list, rather than joining it, so I could step through the element contents.
– directedition
Sep 8 '11 at 14:04
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