input: Write a function that filters out the even numbers from a list of integers and returns only the even numbers. If the list is empty, the function should return an empty list.
  assert filter_even_numbers([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])==[2, 4, 6, 8, 10]
  assert filter_even_numbers([3, 5, 7, 9])==[]
  assert filter_even_numbers([2, 4, 6, 8])==[2, 4, 6, 8]
  assert filter_even_numbers([])==[]
output: def filter_even_numbers(numbers):
      return [num for num in numbers if num % 2 == 0]