A deque object is similar to a list object. The main difference is that operations at a deque's end are faster but operations in between are slower.
from collections import deque
D = deque([ 'one', 'two', 'three', 'four' ])
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# Add items on the deque's right side:
#
D.append('five')
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# Add another item (which happens to be a list):
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D.append([ 'six', 'seven' ])
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# Add an on the deque's left side:
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D.appendleft('zero')
print(D)
#
# deque(['zero', 'one', 'two', 'three', 'four', 'five', ['six', 'seven']])
#
# Remove items on the right side
#
print(D.pop()) # ['six', 'seven']
print(D.pop()) # five
#
# Remove an item on the left side
#
print(D.popleft()) # zero
print(D) # deque(['one', 'two', 'three', 'four'])