Python · Iterators, modules and the standard library

collections.deque

A double-ended queue with fast appends and pops on both ends.

pythonRunnable example python course

Syntax

deque(iterable)

Example

Open in the lab

from collections import deque
queue = deque([1, 2, 3])
queue.appendleft(0)
queue.append(4)
print(list(queue))

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