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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 sky2pix(self, pos):
 """ Convert sky coordinates into pixel coordinates. Parameters pos : (float, float) The (ra, dec) sky coordinates (degrees) Returns ------- pixel : (float, float) The (x,y) pixel coordinates """

        pixel = self.wcs.wcs_world2pix([pos], 1)
        # wcs and pyfits have oposite ideas of x/y
        return [pixel[0][1], pixel[0][0]]