Una cola de dos extremos, o deque, admite la adición y eliminación de elementos de cualquier extremo. Las pilas y colas de uso más común son formas degeneradas de deques, donde las entradas y salidas están restringidas a un solo extremo.
import collections
DoubleEnded = collections.deque(["Mon","Tue","Wed"])
DoubleEnded.append("Thu")
print ("Appended at right - ")
print (DoubleEnded)
DoubleEnded.appendleft("Sun")
print ("Appended at right at left is - ")
print (DoubleEnded)
DoubleEnded.pop()
print ("Deleting from right - ")
print (DoubleEnded)
DoubleEnded.popleft()
print ("Deleting from left - ")
print (DoubleEnded)
Appended at right -
deque(['Mon', 'Tue', 'Wed', 'Thu'])
Appended at right at left is -
deque(['Sun', 'Mon', 'Tue', 'Wed', 'Thu'])
Deleting from right -
deque(['Sun', 'Mon', 'Tue', 'Wed'])
Deleting from left -
deque(['Mon', 'Tue', 'Wed'])