Implement the asyncFilter function, which takes an array of numbers and an asynchronous predicate function, and returns a filtered array. For example, given the input [1, 2, 3] and a function that keeps odd numbers, the output should be [1, 3].

The asyncFilter function should apply an asynchronous predicate to each element of the array either sequentially or in parallel and return a new array with elements for which the predicate returned true. Here is an example implementation in JavaScript using Promise.all for parallel processing:

async function asyncFilter(arr, predicate) {
  const results = await Promise.all(arr.map(predicate));
  return arr.filter((_, index) => results[index]);
}

// Example usage:
async function isOdd(num) {
  return num % 2 !== 0;
}

asyncFilter([1, 2, 3], isOdd).then(filtered => {
  console.log(filtered); // [1, 3]
});

Here, we first run the predicate for all elements, wait for the results, and then filter the original array based on the obtained boolean values.