input: Write a function to find the maximum element in the given array and return it. If the array is empty, return None.
  assert maximize_element([1, 10, 50, 3, 8])==50
  assert maximize_element([])==None
  assert maximize_element([-5, -3, -1, -10])==-1
  assert maximize_element([2, 2, 2, 2])==2
output: def maximize_element(arr):
      if not arr:
          return None
      return max(arr)