function escape(string) {
    return string == null ? '' : (string + '').replace(reUnescapedHtml, escapeHtmlChar);
  }
Converts the characters `&`, `<`, `>`, `"`, and `'` in `string` to their
corresponding HTML entities.

@static
@memberOf _
@category Utilities
@param {String} string The string to escape.
@returns {String} Returns the escaped string.
@example

_.escape('Moe, Larry & Curly');
// => "Moe, Larry &amp; Curly"