code: def create_node(participant_id):
      
      exp = Experiment(session)
  
      # Get the participant.
      try:
          participant = models.Participant.query.filter_by(id=participant_id).one()
      except NoResultFound:
          return error_response(error_type="/node POST no participant found", status=403)
  
      # Make sure the participant status is working
      if participant.status != "working":
          error_type = "/node POST, status = {}".format(participant.status)
          return error_response(error_type=error_type, participant=participant)
  
      # execute the request
      network = exp.get_network_for_participant(participant=participant)
      if network is None:
          return Response(dumps({"status": "error"}), status=403)
  
      node = exp.create_node(participant=participant, network=network)
      assign_properties(node)
      exp.add_node_to_network(node=node, network=network)
  
      # ping the experiment
      exp.node_post_request(participant=participant, node=node)
  
      # return the data
      return success_response(node=node.__json__())
docs: Send a POST request to the node table.
  
      This makes a new node for the participant, it calls:
          1. exp.get_network_for_participant
          2. exp.create_node
          3. exp.add_node_to_network
          4. exp.node_post_request