code: function escape(key) {
    var escapeRegex = /[=:]/g;
    var escaperLookup = {
      '=': '=0',
      ':': '=2'
    };
    var escapedString = ('' + key).replace(escapeRegex, function (match) {
      return escaperLookup[match];
    });
  
    return '$' + escapedString;
  }
docs: Escape and wrap key so it is safe to use as a reactid
  
  @param {string} key to be escaped.
  @return {string} the escaped key.