Python deque extendleft有一个元组？

Question

我有一个deque，最大长度为10.可以.extendleft并添加一个元组。例如：

from collections import deque

x = deque(maxlen = 10)
z = [(1,4),(1,3),(2,5),(7,1),(6,4),(8,2),(9,1),(9,5),(7,3),(8,3)] 
for y in z:
    x.append(y)
print x
x.extendleft((6,7))
print x

返回：

deque([(1, 4), (1, 3), (2, 5), (7, 1), (6, 4), (8, 2), (9, 1), (9, 5), (7, 3), (8, 3)], maxlen=10)
deque([7, 6, (1, 4), (1, 3), (2, 5), (7, 1), (6, 4), (8, 2), (9, 1), (9, 5)], maxlen=10)

我试过了：     对=（6,7）     x.extendleft（对） 结果相同。

Answer 1

In [7]: x.extendleft([(6,7)])

In [8]: x
Out[8]: deque([(6, 7), (1, 4), (1, 3), (2, 5), (7, 1), (6, 4), (8, 2), (9, 1), (9, 5), (7, 3)], maxlen=10)

或更简单：

In [10]: x.appendleft((6, 7))