input: def is_array_even(arr): 
    if len(arr)%2 == 0:
      return True
    else:
      return False
  
  """
  Check if the length of the given array is even.
  >>> is_array_even([1, 2, 3, 4])
  True
  >>> is_array_even([1, 2, 3, 4, 5])
  False
  """
output:     return len(arr) % 2 == 0