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Check if Python Package is installed
... a python script, just do something like this:
Python 3.3+ use sys.modules and find_spec:
import importlib.util
import sys
# For illustrative purposes.
name = 'itertools'
if name in sys.modules:
print(f"{name!r} already in sys.modules")
elif (spec := importlib.util.find_spec(name)) is not None...
How do you cast a List of supertypes to a List of subtypes?
...er to another. However, you can cast through an intermediate wildcard type and it will be allowed (since you can cast to and from wildcard types, just with an unchecked warning):
List<TestB> variable = (List<TestB>)(List<?>) collectionOfListA;
...
What exactly is an “open generic type” in .NET? [duplicate]
I was going through Asp.Net MVC lesson and learned that, for a method to qualify as an action for a controller,
4 Answer...
Git push to wrong branch
Working with git, after some 'commit', and a couple of 'push', I realized that am using the wrong branch !
3 Answers
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What is x after “x = x++”?
...gning the old value of x back into itself.
x = x++;
x++ increments x and returns its old value.
x = assigns the old value back to itself.
So in the end, x gets assigned back to its initial value.
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Is there something like Annotation Inheritance in java?
I'm exploring annotations and came to a point where some annotations seems to have a hierarchy among them.
4 Answers
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iOS: How does one animate to new autolayout constraint (height)
...ith autolayout constraints before. I have a small new app I'm working on and noticed that the NIB's views are defaulting to autolayout. So, I figured I'd take the opportunity to work with it and try to figure out where Apple is going with this.
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How to create a readonly textbox in ASP.NET MVC3 Razor
...mplates. Just call .EditorFor.
While @Shark's solution works correctly, and it is simple and useful, my solution (that I use always) is this one: Create an editor-template that can handles readonly attribute:
Create a folder named EditorTemplates in ~/Views/Shared/
Create a razor PartialView na...
Converting Stream to String and back…what are we missing?
I want to serialize objects to strings, and back.
8 Answers
8
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In Python, using argparse, allow only positive integers
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type would be the recommended option to handle conditions/checks, as in Yuushi's answer.
In your specific case, you can also use the choices parameter if your upper limit is also known:
parser.add_argument('foo', type=int, choices=xrange(5, 10))
Note: Use range ...