def elim_duplicates(og_string, new_string=""):

    # Base case: return when the original gangster string is empty
    if len(og_string) == 0:
        return new_string

    # If the new_string is empty, seed it with the first char from the og_string
    if len(new_string) == 0:
        new_string += og_string[:1]

    # If the first letter in the og_string does NOT equal the last letter
    # we added to the new_string, add the letter to the new_string
    if og_string[0] != new_string[-1]:
        new_string += og_string[0]

    # Recursive case: chop off a letter from the og_string and call the func
    return elim_duplicates(og_string[1:], new_string)