code: def draw(self,N=1.5):
          
          while N>0.5:
              for (l,mvmt) in self.ordering_step():
                  pass
              N = N-1
          if N>0:
              for (l,mvmt) in self.ordering_step(oneway=True):
                  pass
          self.setxy()
          self.draw_edges()
docs: compute every node coordinates after converging to optimal ordering by N
             rounds, and finally perform the edge routing.