code: def centres_from_shape_pixel_scales_and_origin(shape, pixel_scales, origin):
      
  
      y_centre_arcsec = float(shape[0] - 1) / 2 + (origin[0] / pixel_scales[0])
      x_centre_arcsec = float(shape[1] - 1) / 2 - (origin[1] / pixel_scales[1])
  
      return (y_centre_arcsec, x_centre_arcsec)
docs: Determine the (y,x) arc-second central coordinates of an array from its shape, pixel-scales and origin.
  
       The coordinate system is defined such that the positive y axis is up and positive x axis is right.
  
      Parameters
       ----------
      shape : (int, int)
          The (y,x) shape of the 2D array the arc-second centre is computed for.
      pixel_scales : (float, float)
          The (y,x) arc-second to pixel scales of the 2D array.
      origin : (float, flloat)
          The (y,x) origin of the 2D array, which the centre is shifted to.
  
      Returns
      --------
      tuple (float, float)
          The (y,x) arc-second central coordinates of the input array.
  
      Examples
      --------
      centres_arcsec = centres_from_shape_pixel_scales_and_origin(shape=(5,5), pixel_scales=(0.5, 0.5), origin=(0.0, 0.0))