A program that returns a list that contains only the elements that are common between two lists without duplicates.

list_overlap.py

# Prgram which returns list of common elements in two lists.
list_a = [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]
list_b = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]

# Removing duplicates.

def remove_duplicates(any_list):
    new_list = []
    for item in any_list:
        if item not in new_list:
            new_list.append(item)
    return new_list

new_list_a = remove_duplicates(list_a)
new_list_b = remove_duplicates(list_b)

print new_list_a
print new_list_b
    
# Make a new list which contains elements which are common in two lists.
def common_list(list_1, list_2):
    new_common_list = []
    for element in list_1:
        if element in list_2:
            new_common_list.append(element)
    return new_common_list

print common_list(new_list_a, new_list_b)