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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 get_unique_families(hkls):
 """ Returns unique families of Miller indices. Families must be permutations of each other. Args: hkls ([h, k, l]):
 List of Miller indices. Returns: {hkl: multiplicity}: A dict with unique hkl and multiplicity. """

    # TODO: Definitely can be sped up.
    def is_perm(hkl1, hkl2):
        h1 = np.abs(hkl1)
        h2 = np.abs(hkl2)
        return all([i == j for i, j in zip(sorted(h1), sorted(h2))])

    unique = collections.defaultdict(list)
    for hkl1 in hkls:
        found = False
        for hkl2 in unique.keys():
            if is_perm(hkl1, hkl2):
                found = True
                unique[hkl2].append(hkl1)
                break
        if not found:
            unique[hkl1].append(hkl1)

    pretty_unique = {}
    for k, v in unique.items():
        pretty_unique[sorted(v)[-1]] = len(v)

    return pretty_unique