#m = primary matrix
#n = secondary matrix
def mmult(m, n):
    nit = 0
    nitt = 0
    mitt = 0
    s = 0
    ans = []
    if len(m[0]) == len(n):
        while mitt <= len(m)-1:
            row = []
            while nitt <= len(n[0])-1:
                while nit <= len(n)-1:
                    s = s + (m[mitt][nit]*n[nit][nitt])
                    nit=nit+1
                nit = 0
                row.append(s)
                nitt=nitt+1
                s = 0
            nitt=0
            mitt=mitt+1
            ans.append(row)
    else:
        print("Cannot be done, sorry!")
    return ans
m = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
n = [[7, 8, 9], [4, 5, 6], [1, 2, 3]]
print(mmult(m, n))