input: Write a function to print out the largest value from a given list of numbers.
  def get_max_value(numbers):
      return max(numbers)
  
  assert get_max_value([2, 4, 1, 6]) == 6
  assert get_max_value([10, 5, 20, 8]) == 20
  assert get_max_value([9, 3, 7, 1]) == 9
  assert get_max_value([1, 1, 1, 1]) == 1
  assert get_max_value([]) == None
output: def get_max_value(numbers):
      if not numbers:
          return None
      return max(numbers)