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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 heightmap_normalize( hm: np.ndarray, mi: float = 0.0, ma: float = 1.0 ) -> None: """Normalize heightmap values between ``mi`` and ``ma``. Args: mi (float):
 The lowest value after normalization. ma (float):
 The highest value after normalization. """

    lib.TCOD_heightmap_normalize(_heightmap_cdata(hm), mi, ma)