iterating over a deque in two directions efficiently in Python -

i have deque, let's call deq. need iterate on both ends, , not modifying @ during these iterations.

naturally, don't want create another deque. i've considered reversed, don't know if creates copies. if, example, write:

reversed_deq = reversed(deq) 

will reference exact same memory locations, iterate on in reverse, without using more memory/time?

that seems logical way go double-ended queue, want make sure i'm not missing anything.

i can't find code deque (usually have "python equivalent" of these things, couldn't find it), , reason - no matter run - timeit gives me between 15 , 16 ns (for try time, not this)

from c source reversed([deque]) returns reverse iterator, no copies or memory allocation. [deque].reverse() reverse in place.