input: Write a function to find the maximum element in the given array of numbers. The function should return the maximum number as output.
  assert find_max([1, 43, 78, 3, 92, 42])==92
  assert find_max([34, 56, 78, 90])==90
  assert find_max([10, 20, 30, 40])==40
  assert find_max([5, 3, 8, 9, 1])==9
  assert find_max([1, 1, 1, 1])==1
output: def find_max(arr):
      return max(arr)