input: Write a function to filter out even numbers from a given list of integers. The function should return a list containing only the even numbers from the input list. If the input 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([11, 13, 15])==[]
  assert filter_even_numbers([2, 4, 6, 8])==[2, 4, 6, 8]
  assert filter_even_numbers([1, 3, 5])==[]
  assert filter_even_numbers([])==[]
output: def filter_even_numbers(lst):
      return [num for num in lst if num % 2 == 0]