code: def launch_minecraft(ports = [], wait_timeout = 360):
      
      if "MALMO_XSD_PATH" not in os.environ:
          print("Please set the MALMO_XSD_PATH environment variable.")
          return
      cwd = os.getcwd()
      try:
          os.chdir(malmo_install_dir + "/Minecraft")
          launch_minecraft_in_background(os.getcwd(), ports, wait_timeout)
      finally:
          os.chdir(cwd)
docs: Launch Malmo Minecraft Mod in one or more clients from 
         the Minecraft directory on the (optionally) given ports.
         Args:
             ports: an optionsl list of ports to start minecraft clients on. 
             Defaults to a single Minecraft client on port 10000.
             wait_timeout: optional time in seconds to wait (defaults to 3 mins).