var React = require('react');

module.exports = React.createClass({
  render: function() {
    return (
      <h1>{'Hello world!'}</h1>
    );
  }
});

var React = require('react');

module.exports = React.createClass({
  render: function () {
    return (
      <h1>{'Hello world!'}</h1>
    );
  }
});

Add missing espace before parentheses
Add missing espace before parentheses
