Calling list() on permutation

[trevorkavanaugh]

Hello,

Whenever I call list() on a permutations object it removes all of the data from the permutations object. Could anyone explain why that is to me?

Example 1:

from itertools import permutations


perm = permutations([1,2,3])

print(list(perm))

print(len(list(perm)))

Output:
[(1, 2, 3), (1, 3, 2), (2, 1, 3), (2, 3, 1), (3, 1, 2), (3, 2, 1)]
0

Example 2:

from itertools import permutations


perm = permutations([1,2,3])

print(len(list(perm)))

print(list(perm))

Output:
6
[]