code: def flip(self):
          '''
          :returns: None
  
          Swaps the positions of A and B.
          '''
          tmp = self.A.xyz
          self.A = self.B
          self.B = tmf flip(self):
          '''
          :returns: None
  
          Swaps the positions of A and B.
          '''
          tmp = self.A.xyz
          self.A = self.B
          self.B = tmp
docs: :returns: None
  
          Swaps the positions of A and B.