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Add some stuff to lists, tuples, dicts and sets
Lists: added `remove`, `insert` and `index` Tuples: added extended unpacking Dictionaries: added new unpacking from Python 3.5 Sets: added ^, <=, >= operators
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@ -212,6 +212,17 @@ li2 = li[:] # => li2 = [1, 2, 4, 3] but (li2 is li) will result in false.
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# Remove arbitrary elements from a list with "del"
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# Remove arbitrary elements from a list with "del"
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del li[2] # li is now [1, 2, 3]
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del li[2] # li is now [1, 2, 3]
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# Remove first occurrence of a value
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li.remove(2) # li is now [1, 3]
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li.remove(2) # Raises a ValueError as 2 is not in the list
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# Insert an element at a specific index
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li.insert(1, 2) # li is now [1, 2, 3] again
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# Get the index of the first item found
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li.index(2) # => 3
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li.index(4) # Raises a ValueError as 4 is not in the list
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# You can add lists
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# You can add lists
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# Note: values for li and for other_li are not modified.
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# Note: values for li and for other_li are not modified.
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li + other_li # => [1, 2, 3, 4, 5, 6]
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li + other_li # => [1, 2, 3, 4, 5, 6]
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@ -245,6 +256,8 @@ tup[:2] # => (1, 2)
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# You can unpack tuples (or lists) into variables
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# You can unpack tuples (or lists) into variables
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a, b, c = (1, 2, 3) # a is now 1, b is now 2 and c is now 3
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a, b, c = (1, 2, 3) # a is now 1, b is now 2 and c is now 3
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# You can also do extended unpacking
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a, *b, c = (1, 2, 3, 4) # a is now 1, b is now [2, 3] and c is now 4
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# Tuples are created by default if you leave out the parentheses
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# Tuples are created by default if you leave out the parentheses
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d, e, f = 4, 5, 6
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d, e, f = 4, 5, 6
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# Now look how easy it is to swap two values
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# Now look how easy it is to swap two values
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@ -302,6 +315,11 @@ filled_dict.update({"four":4}) #=> {"one": 1, "two": 2, "three": 3, "four": 4}
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# Remove keys from a dictionary with del
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# Remove keys from a dictionary with del
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del filled_dict["one"] # Removes the key "one" from filled dict
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del filled_dict["one"] # Removes the key "one" from filled dict
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# From Python 3.5 you can also use the additional unpacking options
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{'a': 1, **{'b': 2}} # => {'a': 1, 'b': 2}
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{'a': 1, **{'a': 2}} # => {'a': 2}
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# Sets store ... well sets
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# Sets store ... well sets
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empty_set = set()
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empty_set = set()
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@ -328,6 +346,15 @@ filled_set | other_set # => {1, 2, 3, 4, 5, 6}
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# Do set difference with -
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# Do set difference with -
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{1, 2, 3, 4} - {2, 3, 5} # => {1, 4}
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{1, 2, 3, 4} - {2, 3, 5} # => {1, 4}
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# Do set symmetric difference with ^
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{1, 2, 3, 4} ^ {2, 3, 5} # => {1, 4, 5}
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# Check if set on the left is a superset of set on the right
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{1, 2} >= {1, 2, 3} # => False
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# Check if set on the left is a subset of set on the right
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{1, 2} <= {1, 2, 3} # => True
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# Check for existence in a set with in
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# Check for existence in a set with in
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2 in filled_set # => True
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2 in filled_set # => True
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10 in filled_set # => False
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10 in filled_set # => False
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