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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def distinct(l):
 """ Return a list where the duplicates have been removed. Args: l (list):
 the list to filter. Returns: list: the same list without duplicates. """

    seen = set()
    seen_add = seen.add
    return (_ for _ in l if not (_ in seen or seen_add(_)))