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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 _normalize(self):
 """ Make the quaternion unit length. """

        # Get length
        L = self.norm()
        if not L:
            raise ValueError('Quaternion cannot have 0-length.')
        # Correct
        self.w /= L
        self.x /= L
        self.y /= L
        self.z /= L