<s>[INST] Python: how to add the contents of an iterable to a set? What is the "one [...] obvious way" to add all items of an iterable to an existing set?
 [/INST] by set, do you mean set?
>>> foo = set(range(0, 4))
>>> foo
set([0, 1, 2, 3])
>>> foo.update(range(2, 6))
>>> foo
set([0, 1, 2, 3, 4, 5])

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