old_contents: # coding=utf-8
  
  from particles import Particle
  
  class RectParticle(Particle):
      
      def __init__(self, l):
          # Particle.__init__(self, l)
          super(RectParticle, self).__init__(l)
          rectMode(CENTER)
          self.rota = PI/3
      
      def display(self):
          stroke(0, self.lifespan)
          fill(204, 53, 100, self.lifespan)
          with pushMatrix():
              translate(self.location.x, self.location.y)
              rotate(self.rota)
              rect(0, 0, 20, 20)
              self.rota += random(0.02, .10)
  
new_contents: # coding=utf-8
  
  from particles import Particle
  
  class RectParticle(Particle):
      
      def __init__(self, l):
          Particle.__init__(self, l)
          # super(RectParticle, self).__init__(l)
          rectMode(CENTER)
          self.rota = PI/3
      
      def display(self):
          stroke(0, self.lifespan)
          fill(204, 53, 100, self.lifespan)
          with pushMatrix():
              translate(self.location.x, self.location.y)
              rotate(self.rota)
              rect(0, 0, 20, 20)
              self.rota += random(0.02, .10)
  
subject: Update rectparticles.py