code: def check_help_all_output(pkg, subcommand=None):
      """test that `python -m PKG --help-all` works"""
      cmd = [sys.executable, "-m", pkg]
      if subcommand:
          cmd.extend(subcommand)
      cmd.append("--help-all")
      out, err, rc = get_output_error_code(cmd)
      assert rc == 0, err
      assert "Traceback" not in err
      assert "Options" in out
      assert "Class parameters" in out
      return out, err
  
imports: import sys
  from subprocess import Popen, PIPE
label_desc: Use image node_id 3 for calling a global function with example usage: check_help_all_output(pkg, subcommand) and returns: out,  err