Implementing an efficient queue in Python -


i have been trying implement queue in python, , i've been running problem.

i attempting use lists implement queue data structure, can't quite figure out how make enqueue , dequeue o(1) operations.

every example have seen online, seems append enqueue operation , remove first element list dequeue operation. make dequeue operation o(n) (where n size of list) correct?

is there basic have missed? or have use linkedlists implement queue efficiently? 

import unittest  class queue():     def __init__(self):         self._queue = []         self.size = 0         self.maxsize = 10      def enqueue(self, item):         if self.size < self.maxsize:             self._queue.append(item)      def dequeue(self):         '''         removes item front of list. remove first element of         array         '''         first = self._queue[0]         del self._queue[0]         return first


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