class_docstr: Example messenger onboarding world for Echo task, displays.
  
  onboarding worlds that only exist to send an introduction message.
class_docstr_tok: ["Example","messenger","onboarding","world","for","Echo","task",",","displays",".","onboarding","worlds","that","only","exist","to","send","an","introduction","message","."]
code: def generate_world(opt, agents):
      return MessengerEchoOnboardWorld(opt=opt, agent=agents[0])
  
imports: from parlai.core.worlds import World
  from parlai.chat_service.services.messenger.worlds import OnboardWorld
label_desc: Use image node_id 1 for calling the MessengerEchoOnboardWorld obj's underlying member method code with example usage: obj.generate_world(opt, agents) and returns: MessengerEchoOnboardWorld