text: 
  class NopBackpressureManager:
      def __init__(self):
          pass
  
      def register_pressure(self):
          pass
  
      def unregister_pressure(self):
          pass
  
      def reached(self) -> bool:
          return False
  
  
  class BackpressureManager:
  
      def __init__(self, max):
          self.max = max
          self.pressure = 0
  
      def register_pressure(self):
          self.pressure += 1
  
      def unregister_pressure(self):
          self.pressure -= 1
  
      def reached(self) -> bool:
          return self.pressure >= self.max
  