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Access multiple elements of list knowing their index

...3, 8, 5, 6]) b = [1, 2, 5] print(list(a[b])) # Result: [1, 5, 5] But really, your current solution is fine. It's probably the neatest out of all of them. share | improve this answer | ...
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What does “hashable” mean in Python?

...y and a set member, because these data structures use the hash value internally. All of Python’s immutable built-in objects are hashable, while no mutable containers (such as lists or dictionaries) are. Objects which are instances of user-defined classes are hashable by default; they all comp...
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Calling class staticmethod within the class body?

... def stat_func(): return 42 _ANS = stat_func.__func__() # call the staticmethod def method(self): ret = Klass.stat_func() return ret As an aside, though I suspected that a staticmethod object had some sort of attribute storing the original function, I had no ...
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How to get the client IP address in PHP [duplicate]

...se addresses are larger than the older IPv4 addresses. (Note that IPv6 usually uses 39 characters at most but there is also a special IPv6 notation for IPv4 addresses which in its full form can be up to 45 characters. So if you know what you are doing you can use 39 characters, but if you just want...
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Why doesn't Python have a sign function?

... it wasn't accepted, because they didn't agree on what it should return in all the edge cases (+/-0, +/-nan, etc) So they decided to implement only copysign, which (although more verbose) can be used to delegate to the end user the desired behavior for edge cases - which sometimes might require the...
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How does deriving work in Haskell?

Algebraic Data Types (ADTs) in Haskell can automatically become instances of some typeclasse s (like Show , Eq ) by deriving from them. ...
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Resolve build errors due to circular dependency amongst classes

...ember that the .cc and not the .h is the unit of compilation), you need to allocate space for object A. So, well, how much space then? Enough to store B! What's the size of B then? Enough to store A! Oops. Clearly a circular reference that you must break. You can break it by allowing the compiler ...
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In what areas might the use of F# be more appropriate than C#? [closed]

... sweet spot for the language within enterprise software, namely algorithmically complex analysis of large data sets. My experience has been a very positive one. In particular: Units of measure The industry I work in is littered with units. The equations I implemented (often of a geometric nature) d...
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Remove duplicate elements from array in Ruby

... array = array.uniq uniq removes all duplicate elements and retains all unique elements in the array. This is one of many beauties of the Ruby language. share | ...
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Stop pip from failing on single package when installing with requirements.txt

I am installing packages from requirements.txt 6 Answers 6 ...