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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_lattice_type(number):
 """Return the lattice crystal system. Hexagonal cells are differentiated into rhombohedral and hexagonal lattices. Args: number (int):
 The international space group number. Returns: str: The lattice crystal system. """

        f = lambda i, j: i <= number <= j
        cs = {'triclinic': (1, 2), 'monoclinic': (3, 15),
              'orthorhombic': (16, 74), 'tetragonal': (75, 142),
              'trigonal': (143, 167), 'hexagonal': (168, 194),
              'cubic': (195, 230)}

        crystal_system = None
        for k, v in cs.items():
            if f(*v):
                crystal_system = k
                break

        if number in [146, 148, 155, 160, 161, 166, 167]:
            return "rhombohedral"
        elif crystal_system == "trigonal":
            return "hexagonal"
        else:
            return crystal_system