Matrix multiplication in python

Hello,
I have an issue finding the code to calculate the product of two matrices. Here is my code:

def multiply(m1, m2):
m = []
if len(m1[0]) != len(m2):
return False
for i in range(len(m1)):
ligne = []
for j in range(len(m2[0])):
for k in range(len(m1[0])):
element = m1[i][j] * m2[i][j]
element = element + m1[i][k] * m2[k][i]
ligne.append(element)
m.append(ligne)
return m

I run this program with the following lists:
m1 = [[0,0,0],[2,1,1],[2,1,1]]
m2 = [[3,2,1],[3,3,0],[0,1,2]]

and it returns: [[0, 0, 0], [7, 4, 1], [2, 3, 4]] except for the first line, the rest is wrong, but where is the error??? Please help!!!

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