input: def filter_even_numbers(numbers):
      """Filter out all the even numbers from a given list of integers.
      >>> filter_even_numbers([3, 4, 5, 6, 7])
      [4, 6]
      """
      even_numbers = []
      for i in numbers:
          if i % 2 == 0:
              even_numbers.append(i)
      return even_numbers
output:     even_numbers = []
      for i in numbers:
          if i % 2 == 0:
              even_numbers.append(i)
      return even_numbers