python NZEC error

import math;
T=int(raw_input());
a=[];
for i in range(T):
    a=raw_input().split();
    N=int(a[0]);
    M=int(a[1]);
    K=int(a[2]);
    n=math.factorial(N+M-2)/(math.factorial(N-1)*math.factorial(M-1));

    a=math.factorial(N+M-3)/(math.factorial(N-1)*math.factorial(M-2));
    print n;
    print a;

Why is this code giving me an NZEC error?