input: Write a python function to split an array into even and odd numbers.
  assert split_even_odd([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])==([2, 4, 6, 8, 10], [1, 3, 5, 7, 9])
  assert split_even_odd([10, 20, 45, 67, 84, 93])==([10, 20, 84], [45, 67, 93])
  assert split_even_odd([5, 7, 9, 8, 6, 4, 3])==([8, 6, 4], [5, 7, 9, 3])
output: def split_even_odd(arr):
      evens = [x for x in arr if x % 2 == 0]
      odds = [x for x in arr if x % 2 != 0]
      return evens, odds