unique_in_order.py

"""
Implement the function unique_in_order which takes as argument a sequence and returns a list of items without any elements with the same value next to each other and preserving the original order of elements.

For example:

unique_in_order('AAAABBBCCDAABBB') == ['A', 'B', 'C', 'D', 'A', 'B']
unique_in_order('ABBCcAD')         == ['A', 'B', 'C', 'c', 'A', 'D']
unique_in_order([1,2,2,3,3])       == [1,2,3]
"""


def unique_in_order(iterable):
    ll = []
    for x in iterable:
        if len(ll) == 0:
            ll.append(x)
        if ll[-1] != x:
            ll.append(x)
    return ll

iterable='AAAABBBCCDAABBB'#), ['A','B','C','D','A','B'])
print(unique_in_order(iterable))