code: def get_beam(self, ra, dec):
          
          # check to see if we need to scale the major axis based on the declination
          if self.lat is None:
              factor = 1
          else:
              # this works if the pa is zero. For non-zero pa it's a little more difficult
              factor = np.cos(np.radians(dec - self.lat))
          return Beam(self.beam.a / factor, self.beam.b, self.beam.pa)
docs: Determine the beam at the given sky location.
  
          Parameters
          ----------
          ra, dec : float
              The sky coordinates at which the beam is determined.
  
          Returns
          -------
          beam : :class:`AegeanTools.fits_image.Beam`
              A beam object, with a/b/pa in sky coordinates