The math.perm() function computes the number of ways to choose k items from n items with order and without repetition. 

math.perm(n, k = None)

The optional parameter k, if not specified,  defaults to n.
The function returns the value of  n! / (n - k)!  when k <= n . If k > n, the function returns  zero.

import math

print(math.perm(10, 3))
print(math.perm(14, 7))
print(math.perm(100, 10))

The function  raises TypeError if either of the arguments are not integers. A ValueError if either of the arguments are negative.

import math
math.perm('5', 5)
import math

math.perm(-10, 2)