code: function trim(string, chars) {
        string = string == null ? '' : String(string);
        if (!string) {
          return string;
        }
        if (chars == null) {
          return string.slice(trimmedLeftIndex(string), trimmedRightIndex(string) + 1);
        }
        chars = String(chars);
        return string.slice(charsLeftIndex(string, chars), charsRightIndex(string, chars) + 1);
      }
docs: Removes leading and trailing whitespace or specified characters from `string`.
  
  @static
  @memberOf _
  @category Strings
  @param {string} [string=''] The string to trim.
  @param {string} [chars=whitespace] The characters to trim.
  @returns {string} Returns the trimmed string.
  @example
  
  _.trim('  fred  ');
  // => 'fred'
  
  _.trim('-_-fred-_-', '_-');
  // => 'fred'