old_contents: 
  # Copyright (c) Twisted Matrix Laboratories.
  # See LICENSE for details.
  #
  # From https://twistedmatrix.com/documents/current/_downloads/simpleserv.py
  
  
  from twisted.internet import reactor, protocol
  
  import rollbar
  
  
  def bar(p):
      # These local variables will be sent to Rollbar and available in the UI
      a = 33
      b = a * 5
      baz()
  
  
  def foo():
      hello = 'world'
      bar(hello)
  
  
  class Echo(protocol.Protocol):
      """This is just about the simplest possible protocol"""
  
      def dataReceived(self, data):
          "As soon as any data is received, write it back."
  
          # Cause an uncaught exception to be sent to Rollbar
          foo()
          self.transport.write(data)
  
  
  def main():
      rollbar.init('ACCESS_TOKEN', environment='test', handler='twisted')
  
      """This runs the protocol on port 8000"""
      factory = protocol.ServerFactory()
      factory.protocol = Echo
      reactor.listenTCP(8000, factory)
      reactor.run()
  
  
  # this only runs if the module was *not* imported
  if __name__ == '__main__':
      main()
  
new_contents: 
  # Copyright (c) Twisted Matrix Laboratories.
  # See LICENSE for details.
  #
  # From https://twistedmatrix.com/documents/current/_downloads/simpleserv.py
  
  # NOTE: pyrollbar requires both `Twisted` and `treq` packages to be installed
  
  from twisted.internet import reactor, protocol
  
  import rollbar
  
  
  def bar(p):
      # These local variables will be sent to Rollbar and available in the UI
      a = 33
      b = a * 5
      baz()
  
  
  def foo():
      hello = 'world'
      bar(hello)
  
  
  class Echo(protocol.Protocol):
      """This is just about the simplest possible protocol"""
  
      def dataReceived(self, data):
          "As soon as any data is received, write it back."
  
          # Cause an uncaught exception to be sent to Rollbar
          foo()
          self.transport.write(data)
  
  
  def main():
      rollbar.init('ACCESS_TOKEN', environment='test', handler='twisted')
  
      """This runs the protocol on port 8000"""
      factory = protocol.ServerFactory()
      factory.protocol = Echo
      reactor.listenTCP(8000, factory)
      reactor.run()
  
  
  # this only runs if the module was *not* imported
  if __name__ == '__main__':
      main()
  
subject: Add note about required additional packages installation