Practical Queues and Sliding Windows with Python deque
Many programs need a sequence that changes at both ends. A worker may append new jobs on the right and consume the oldest job from the left. A monitoring loop may keep only the most recent measurements. An algorithm may need to add or remove candidates from either side while scanning an input stream. A Python list is excellent when random access and operations near the right end dominate. It is a poor fit for a FIFO queue that repeatedly removes index zero, because the remaining list elements must be shifted. The collections.deque type is designed for efficient appends and pops at both ends.