text: # Function to check if a Diastema Playbook is Valid
  
  def playbook_check(playbook, diastema_token):
      """
      A set of rules.
      Returns True is Playbook is ok. 
      Or False if there is a problem in the playbook.
      """
  
      if playbook is None:
          print("[ERROR] No Diastema playbook given!")
          return (False, "No Diastema playbook given!")
      
      if not ("diastema-token" in playbook):
          print("[ERROR] No Diastema Token given!")
          return (False, "No Diastema Token given!")
  
      if playbook["diastema-token"] != diastema_token:
          print("[ERROR] Invalid Diastema Token!")
          return (False, "Invalid Diastema Token!")
  
      # More rules can be added here
  
      return (True, "Valid playbook")