private function validate_input( $assoc_args, $grouping ) {
		// Check if valid arguments were passed.
		$arg_match = preg_grep( '/^set-(\w+)/i', array_keys( $assoc_args ) );

		// Verify passed-arguments.
		if ( empty( $grouping ) && empty( $arg_match ) ) {
			WP_CLI::error( 'No valid arguments passed.' );
		}

		// Check whether passed arguments contain value or not.
		$assoc_arg_values = array_filter( array_intersect_key( $assoc_args, array_flip( $arg_match ) ) );

		if ( empty( $grouping ) && empty( $assoc_arg_values ) ) {
			WP_CLI::error( 'No value passed to arguments.' );
		}
	}