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                <form id="weather-data" name="weather" action="" method="get">
  <label for="city">Select a city</label>
  <select id="city" name="city">
    <option value="london">London</option>
    <option value="birmingham">Birmingham</option>
    <option value="cambridge">Cambridge</option>
    <option value="sheffield">Sheffield</option>
  <button type="submit">Get weather</button>




                const citySelector = document.getElementById("city");
const weatherForm = document.getElementById("weather-data");

let abortController;
let lastSelectedCity;

citySelector.addEventListener("change", (event) => {
  console.log(`Weather data request for ${lastSelectedCity} aborted.`);
  console.log("New selected city is: ", citySelector.value);

weatherForm.addEventListener("submit", (event) => {

  abortController = new AbortController();
  const { signal } = abortController;

  const baseURL = "";

  const formData = new FormData(weatherForm);
  const city = formData.get("city");
  lastSelectedCity = city;

  fetch(`${baseURL}/?city=${city}&delay=5000`, { signal })
    .then((response) => {
      if (!response.ok) {
        throw new Error(`HTTP error: ${response.status}`);

      return response.json();
    .then((json) => {
    .catch((err) => {
      if ( === "AbortError") {"Cancelled previous fetch request");
      } else {
        // if it was not an AbortError, throw the error so it propagates
        throw err;