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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 is_filled(self, point):
 """ Query a point to see if the voxel cell it lies in is filled or not. Parameters point: (3,) float, point in space Returns --------- is_filled: bool, is cell occupied or not """

        index = self.point_to_index(point)
        in_range = (np.array(index) < np.array(self.shape)).all()
        if in_range:
            is_filled = self.matrix[index]
        else:
            is_filled = False
        return is_filled