code: def isometric(lat: float, ell: Ellipsoid = None, deg: bool = True):
      
  
      if ell is None:
          ell = Ellipsoid()
  
      f = ell.f  # flattening of ellipsoid
  
      if deg is True:
          lat = np.deg2rad(lat)
  
      e2 = f * (2 - f)  # eccentricity-squared
      e = np.sqrt(e2)  # eccentricity of ellipsoid
  
      x = e * np.sin(lat)
      y = (1 - x) / (1 + x)
      z = np.pi / 4 + lat / 2
  
  #   calculate the isometric latitude
      isolat = np.log(np.tan(z) * (y**(e / 2)))
  
      if deg is True:
          isolat = np.degrees(isolat)
  
      return isolat
docs: computes isometric latitude of a point on an ellipsoid
  
       Parameters
       ----------
  
       lat : float or numpy.ndarray of float
           geodetic latitude
       ell : Ellipsoid, optional
           reference ellipsoid (default WGS84)
       deg : bool, optional
           degrees input/output  (False: radians in/out)
  
       Returns
       -------
  
       isolat : float or numpy.ndarray of float
           isometric latiude
  
       Notes
       -----
  
       Isometric latitude is an auxiliary latitude proportional to the spacing
       of parallels of latitude on an ellipsoidal mercator projection.
  
       Based on Deakin, R.E., 2010, 'The Loxodrome on an Ellipsoid', Lecture Notes,
       School of Mathematical and Geospatial Sciences, RMIT University,
       January 2010