code: def test_help(caplog, capsys, command_tuples):
      with caplog.at_level(logging.INFO), pytest.raises(
          SystemExit
      ) as e:
          main([*command_tuples, "--help"])
      assert e.value.code == 0
      assert not caplog.text
  
      out, err = capsys.readouterr()
  
      # validate metavars are all in lowercase
      usage = "\n".join(takewhile(lambda o: bool(o), out.splitlines()))
  
      message = (
          "metavars not lowercased, you are likely missing formatter_class=XXX "
          "in the command, where XXX should be any of the classes from "
          "`dvc.cli.formatter`, which automatically lowercases metavars.\n"
          "\nExample:\n"
          "\nfrom dvc.cli import formatter\n"
          "\nparser.add_parser(..., formatter_class=formatter.TextHelpFormatter)\n"
      )
      assert not re.findall(
          r"\b[A-Z]{2,}\b", usage, re.MULTILINE
      ), message
  
      assert not err
      assert out
  
file_path: dvc/tests/unit/command/test_help.py
imports: import logging
  import re
  from argparse import SUPPRESS, ArgumentParser
  from itertools import takewhile
  from typing import Tuple
  import pytest
  import shtab
  from dvc.cli import main
  from dvc.cli.parser import get_main_parser
label_desc: Use image node_id 3 for calling a global function with example usage: test_help(caplog, capsys, command_tuples) without return types