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Bidirectional 1 to 1 Dictionary in C#

...gt;, IDictionary { private readonly IDictionary<TFirst, TSecond> _firstToSecond = new Dictionary<TFirst, TSecond>(); [NonSerialized] private readonly IDictionary<TSecond, TFirst> _secondToFirst = new Dictionary<TSecond, TFirst>(); [NonSerialized] private r...
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How to find all the subclasses of a class given its name?

...ses (i.e. subclassed from object, which is the default in Python 3) have a __subclasses__ method which returns the subclasses: class Foo(object): pass class Bar(Foo): pass class Baz(Foo): pass class Bing(Bar): pass Here are the names of the subclasses: print([cls.__name__ for cls in Foo.__subcla...
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Difference between __str__ and __repr__?

What is the difference between __str__ and __repr__ in Python? 23 Answers 23 ...
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Multiple levels of 'collection.defaultdict' in Python

... @ScienceFriction Anything specific that you need help with? When d[new_key] is accessed, it will call the lambda which will create a new defaultdict(int). And when d[existing_key][new_key2] is accessed, a new int will be created. – interjay Oct 11 '13 at 1...
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What are the mechanics of short string optimization in libc++?

... The libc++ basic_string is designed to have a sizeof 3 words on all architectures, where sizeof(word) == sizeof(void*). You have correctly dissected the long/short flag, and the size field in the short form. what value would __min_cap, ...
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what does the __file__ variable mean/do?

... When a module is loaded from a file in Python, __file__ is set to its path. You can then use that with other functions to find the directory that the file is located in. Taking your examples one at a time: A = os.path.join(os.path.dirname(__file__), '..') # A is the par...
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Python memoising/deferred lookup property decorator

... from boltons.cacheutils import cachedproperty class Foo(object): def __init__(self): self.value = 4 @cachedproperty def cached_prop(self): self.value += 1 return self.value f = Foo() print(f.value) # initial value print(f.cached_prop) # cached property is c...
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How to enumerate an object's properties in Python?

... print(property, ":", value) Be aware that in some rare cases there's a __slots__ property, such classes often have no __dict__. share | improve this answer | follow ...
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How do I initialize the base (super) class?

... and invoke their base class through super(), e.g. class X(object): def __init__(self, x): pass def doit(self, bar): pass class Y(X): def __init__(self): super(Y, self).__init__(123) def doit(self, foo): return super(Y, self).doit(foo) Because python knows about old- an...
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correct way to use super (argument passing)

...ich unlike object, absorbs/ignores arguments: class Base(object): def __init__(self, *args, **kwargs): pass class A(Base): def __init__(self, *args, **kwargs): print "A" super(A, self).__init__(*args, **kwargs) class B(Base): def __init__(self, *args, **kwargs): ...