content: import React from 'react';
  import PropTypes from 'prop-types';
  
  const TodoItem = ({ _id, todo, completed, onClick }) => { /* state.todos.[_id/todo/completed] and handleTodoClick from TodoList via App are on the props object */
      return (
          <li
              key={_id}
              style={{
                  textDecoration: completed ? 'line-through' : 'none'
              }}
              onClick={() => onClick(_id, completed)}
          >
              {todo}
          </li>
      );
  };
  TodoItem.propTypes = {
      _id: PropTypes.number.isRequired,
      todo: PropTypes.string.isRequired,
      completed: PropTypes.bool.isRequired,
      onClick: PropTypes.func.isRequired,
  };
  
  export default TodoItem;