content: #!/usr/bin/env python
  
  """Echo server using the threading API."""
  
  from websockets.sync.server import serve
  
  
  def echo(websocket):
      for message in websocket:
          websocket.send(message)
  
  
  def main():
      with serve(echo, "localhost", 8765) as server:
          server.serve_forever()
  
  
  if __name__ == "__main__":
      main()
  