code: def midpoint_refine_triangulation_by_vertices(self, vertices):
          
  
          mlons, mlats = self.segment_midpoints_by_vertices(vertices=vertices)
  
          lonv1 = np.concatenate((self.lons, mlons), axis=0)
          latv1 = np.concatenate((self.lats, mlats), axis=0)
  
          return lonv1, latv1
docs: return points defining a refined triangulation obtained by bisection of all edges
          in the triangulation connected to any of the vertices in the list provided