docstr: Add the output subparser: manage.py output
docstr_tok: ["Add","the","output","subparser",":","manage.py","output"]
code: def setup_subparser(cls, subparser):
      """Add the output subparser: manage.py output"""
      output_subparsers = subparser.add_subparsers()
  
      for subcommand in cls._subcommands().values():
          subcommand.setup_subparser(output_subparsers)
  
imports: import json
  from streamalert.shared.logger import get_logger
  from streamalert.alert_processor.outputs.output_base import StreamAlertOutput, OutputCredentialsProvider
  from streamalert_cli.helpers import user_input, response_is_valid
  from streamalert_cli.outputs.helpers import output_exists
  from streamalert_cli.utils import CLICommand, generate_subparser
label_desc: Use image node_id 1 for calling the OutputCommand obj's underlying member method code with example usage: obj.setup_subparser(cls, subparser) without return types