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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 common(l1: list, l2: list):
    """Return sorted unique common elements for two lists. [1, 5, 653] [2, 3] """
    ret = set()
    for e1 in l1:
        for e2 in l2:
            if e1 == e2:
                ret.add(e1)
    return sorted(list(ret))
