q = [0]
while any(q):
q.pop()
# after while loop, the q is [0] still.
q = [0,1,2]
while any(q):
q.pop()
# after while loop, the q is [0].
q = [None] * 8
while any(q):
q.pop()
# after while loop, the q is [None, None, None, None, None, None, None, None]
q = [0]
while q:
q.pop()
# after while loop, the q is []
q = [None] * 8
while q:
q.pop()
# after while loop, the q is []
