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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 get_cel_to_gal_angle(skydir):
 """Calculate the rotation angle in radians between the longitude axes of a local projection in celestial and galactic coordinates. Parameters skydir : `~astropy.coordinates.SkyCoord` Direction of projection center. Returns ------- angle : float Rotation angle in radians. """

    wcs0 = create_wcs(skydir, coordsys='CEL')
    wcs1 = create_wcs(skydir, coordsys='GAL')
    x, y = SkyCoord.to_pixel(SkyCoord.from_pixel(1.0, 0.0, wcs0), wcs1)
    return np.arctan2(y, x)