Birthday Problem

from math import factorial as f
def perm(n,k):
    P = f(n)/f(n-k)
    return P

def bpro(k): #calculates probability of 'k' people having birthday on the same day, not considering feb 29th. 
    p = (perm(365,k))/ 365**k
    q = 1 - p
    return q