code: function getGid(groupname, options) {
    const gid = _.tryOnce(findGroup(groupname, options), 'id');
    return _.isUndefined(gid) ? null : gid;
  }
docs: Get group GID
  @function $os~getGid
  @param {string} groupname
  @param {Object} [options]
  @param {boolean} [options.refresh=true] - Setting this to false allows operating over a cached database of groups,
  for improved performance. It may result in incorrect results if the affected group changes
  @param {boolean} [options.throwIfNotFound=true] - By default, this function throws an error if the specified group
  cannot be found
  @returns {number|null} - The group ID or null, if it cannot be found
  @example
  // Get GID of 'mysql' group
  $os.getGid('mysql');
  // => 1001