Finding a union of lists of lists in Python

Question

Suppose we have

 temp1 = [1, 2, 3]
 temp2 = [1, 2, 3]
 temp3 = [3, 4, 5]

How do I get the union of the three temporary variables?

Expec

Answer 1

I created a matrix to change the code easily for a generalized input:

temp1=[1,2,3]
temp2=[3,2,6]
temp3=[1,2,3]
matrix = [temp1, temp2, temp3]

result = []
for l in matrix:
    if l not in result:
        result.append(l)

print result