1. extend（iterable）： - 此函数用于在双端队列的右端添加多个值。传递的参数是可迭代的。

2. extendleft（iterable）： - 此函数用于在双端队列的左端添加多个值。传递的参数是可迭代的。由于左侧附加，订单被撤销。

3. reverse（）： - 此函数用于反转 deque元素的顺序。

4. rotate（）： - 此函数按参数中指定的数字旋转双端队列。如果指定的数字为负数，则向左旋转。其他轮换是正确的。

# Python code to demonstrate working of

# extend(), extendleft(), rotate(), reverse()

# importing "collections" for deque operations

import collections

# initializing deque

de = collections.deque([1, 2, 3,])

# using extend() to add numbers to right end

# adds 4,5,6 to right end

de.extend([4,5,6])

# printing modified deque

print ("The deque after extending deque at end is : ")

print (de)

# using extendleft() to add numbers to left end

# adds 7,8,9 to right end

de.extendleft([7,8,9])

# printing modified deque

print ("The deque after extending deque at beginning is : ")

print (de)

# using rotate() to rotate the deque

# rotates by 3 to left

de.rotate(-3)

# printing modified deque

print ("The deque after rotating deque is : ")

print (de)

# using reverse() to reverse the deque

de.reverse()

# printing modified deque

print ("The deque after reversing deque is : ")

print (de)