all Python 3Sets (set)function

set.intersection_update

set theory

Keep only elements found in all the others (in-place intersection).

Syntax

s.intersection_update(*others)

It shrinks the set in place and returns None, so chaining the call or assigning its result is a mistake. Every name bound to that same set sees the trimmed version; if you still need the original contents, use intersection() and store the result in a new variable.

Examples

s = {1, 2, 3, 4}
s.intersection_update({2, 3, 5})
print(sorted(s))   # → [2, 3]

See also

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