闭包内的长函数名

我正在阅读本文，并试图理解此代码

function getRandomNumber(start = 1, end = 10) {
  //works when both start and end are >=1
  return (parseInt(Math.random() * end) % (end - start + 1)) + start;
}
var promiseTRRARNOSG = (promiseThatResolvesRandomlyAfterRandomNumnberOfSecondsGenerator = function() {
  return new Promise(function(resolve, reject) {
    let randomNumberOfSeconds = getRandomNumber(2, 10);
    setTimeout(function() {
      let randomiseResolving = getRandomNumber(1, 10);
      if (randomiseResolving > 5) {
        resolve({
          randomNumberOfSeconds: randomNumberOfSeconds,
          randomiseResolving: randomiseResolving
        });
      } else {
        reject({
          randomNumberOfSeconds: randomNumberOfSeconds,
          randomiseResolving: randomiseResolving
        });
      }
    }, randomNumberOfSeconds * 1000);
  });
});
var testProimse = promiseTRRARNOSG();
testProimse.then(function(value) {
  console.log("Value when promise is resolved : ", value);
});
testProimse.catch(function(reason) {
  console.log("Reason when promise is rejected : ", reason);
});
// Let us loop through and create ten different promises using the function to see some variation. Some will be resolved and some will be rejected. 
for (i=1; i<=10; i++) {
  let promise = promiseTRRARNOSG();
  promise.then(function(value) {
    console.log("Value when promise is resolved : ", value);
  });
  promise.catch(function(reason) {
    console.log("Reason when promise is rejected : ", reason);
  });
}

在这里，作者做了类似的事情var promiseTRRARNOSG = (promiseThatResolvesRandomlyAfterRandomNumnberOfSecondsGenerator = function() {，我无法理解。

有人可以帮助我理解这一行吗？我的意思是明确指出那行代码/声明。