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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 point_lm(self, context):
 """ Supply point source lm coordinates to montblanc """


        # Shape (npsrc, 2)
        (ls, us), _ = context.array_extents(context.name)
        return np.asarray(lm_coords[ls:us], dtype=context.dtype)