circular_buffer_deque.py

from collections import deque

class CircularBuffer (deque):
    """ Creates a circular buffer class which inherits the deque collection 
    and implements extract functions"""
    
    def extract(self,n):
        """ Extracts n items from the right """
        return list([self.pop() for i in range(n)])
    
    def extractleft(self, n):
        """ Extracts n items from the left """
        return list(reversed([self.popleft() for i in range(n)]))
        
        
buffer = CircularBuffer([0],maxlen=100)

buffer.extend([1,2,3,4,5])
print(buffer)
a = buffer.extract(3)
print(a)
print(buffer)

a = buffer.extractleft(2)
print(a)
print(buffer)