content: import React from 'react';
  import createShallow from './createShallow';
  
  const shallow = createShallow();
  
  // Helper function to extract the classes from a styleSheet.
  export default function getClasses(element) {
    const { useStyles } = element.type;
  
    let classes;
    function Listener() {
      classes = useStyles(element.props);
      return null;
    }
    shallow(<Listener />);
  
    return classes;
  }
  