a = [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]
b = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]

common = []

# Build list that contains elems that are common without duplicates

# common elems
for i in a:
   if i in b:
       if i not in common:
        common.append(i)

print(common)