var fs = require('fs');
var timestamp = new Date().toString();
fs.writeFile('date.txt', timestamp, function (err) {
 if (err) throw err;
 fs.readFile('date.txt', function (err, contents) {
 if (err) throw err;
 console.log('Checking the contents'); // 2
 console.log(contents);
 console.assert(contents == timestamp); // 3
 });
});
console.log('I am the last line of the script'); // 1