code: def einstein_mass_in_units(self, unit_mass='angular', critical_surface_density=None):
          
  
          if self.has_mass_profile:
              return sum(
                  map(lambda p: p.einstein_mass_in_units(unit_mass=unit_mass,
                                                         critical_surface_density=critical_surface_density),
                      self.mass_profiles))
          else:
              return None
docs: The Einstein Mass of this galaxy, which is the sum of Einstein Radii of its mass profiles.
  
          If the galaxy is composed of multiple ellipitcal profiles with different axis-ratios, this Einstein Mass \
          may be inaccurate. This is because the differently oriented ellipses of each mass profile