old_contents: import React from 'react';
  import classnames from 'classnames';
  import './modal-container.scss';
  
  const ModalContainer = (props) => {
  	if (! props.children) {
  		return null;
  	}
  
  	return (
  		<div className="modal-container">
  			{props.children}
  		</div>
  	);
  };
  
  export default ModalContainer;
  
new_contents: import React from 'react';
  import PropTypes from 'prop-types';
  
  import './modal-container.scss';
  
  const ModalContainer = (props) => {
    if (! props.children) {
      return null;
    }
  
    return (
      <div className="modal-container">
        {props.children}
      </div>
    );
  };
  
  ModalContainer.propTypes = {
    children: PropTypes.node,
  };
  
  ModalContainer.defaultProps = {
    children: null,
  };
  
  export default ModalContainer;
  
subject: Add proptype validation and clean up ModalContainer component