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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 sph_midpoint(coord1, coord2):
 """Compute the midpoint between two points on the sphere. Parameters coord1 : `~astropy.coordinates.SkyCoord` Coordinate of one point on a great circle. coord2 : `~astropy.coordinates.SkyCoord` Coordinate of the other point on a great circle. Returns ------- midpt : `~astropy.coordinates.SkyCoord` The coordinates of the spherical midpoint. """

    c1 = coord1.cartesian / coord1.cartesian.norm()

    coord2 = coord2.transform_to(coord1.frame)
    c2 = coord2.cartesian / coord2.cartesian.norm()

    midpt = 0.5 * (c1 + c2)
    usph = midpt.represent_as(coord.UnitSphericalRepresentation)

    return coord1.frame.realize_frame(usph)