code: def validate_text(ctx, param, text):
      
      if not text and 'file' not in ctx.params:
          # No <text> and no <file>
          raise click.BadParameter(
              "<text> or -f/--file <file> required")
      if text and 'file' in ctx.params:
          # Both <text> and <file>
          raise click.BadParameter(
              "<text> and -f/--file <file> can't be used together")
      return text
docs: Validation callback for the <text> argument.
      Ensures <text> (arg) and <file> (opt) are mutually exclusive