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not None test in Python [duplicate]
...with default parameters. is tests identity in Python. Because there is one and only one instance of None present in a running Python script/program, is is the optimal test for this. As Johnsyweb points out, this is discussed in PEP 8 under "Programming Recommendations".
As for why this is preferred...
Get the key corresponding to the minimum value within a dictionary
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what if two different keys have the same value? and they happen to both be the smallest value? how can you make it return both?
– user3226932
Dec 18 '16 at 4:29
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Prevent ViewPager from destroying off-screen views
...2, so that when you are on the third page, the first one is not destroyed, and vice-versa.
mViewPager = (ViewPager)findViewById(R.id.pager);
mViewPager.setOffscreenPageLimit(2);
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How can I manually generate a .pyc file from a .py file
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You can use compileall in the terminal. The following command will go recursively into sub directories and make pyc files for all the python files it finds. The compileall module is part of the python standard library, so you don't need to install anything extra to use it. This work...
Django removing object from ManyToMany relationship
...jango's Relations Docs
Note: you might have to get an instance of my_mood and my_interest using Django's QuerySet API before you can execute this code.
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How to simulate target=“_blank” in JavaScript
When a user clicks on a link, I need to update a field in a database and then open the requested link in a new window. The update is no problem, but I don't know how to open a new window without requiring them to click on another hyperlink.
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How to use Comparator in Java to sort
... things with your example class:
it's called People while it has a price and info (more something for objects, not people);
when naming a class as a plural of something, it suggests it is an abstraction of more than one thing.
Anyway, here's a demo of how to use a Comparator<T>:
public c...
Undefined reference to `pow' and `floor'
...calculator in C but when compiling gcc tells me that I'm missing the pow and floor functions. What's wrong?
6 Answers
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Test if object implements interface
...eding to cast afterward with the first one thus giving you two casts ("is" and then an explicit cast). With the second approach you only cast once.
– Andrew Hare
Jan 4 '09 at 6:02
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Struct inheritance in C++
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Other than what Alex and Evan have already stated, I would like to add that a C++ struct is not like a C struct.
In C++, a struct can have methods, inheritance, etc. just like a C++ class.
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