input: Write a function to find the maximum of three numbers. If the given numbers are equal, return any one of them.
  
  def max_of_three(a, b, c):
      if a > b and a > c:
          return a
      elif b > a and b > c:
          return b
      else:
          return c
  
  assert max_of_three(3, 4, 5) == 5
  assert max_of_three(10, 2, 9) == 10
  assert max_of_three(7, 7, 7) == 7
  assert max_of_three(2, 3, 3) == 3
output: def max_of_three(a, b, c):
      if a > b and a > c:
          return a
      elif b > a and b > c:
          return b
      else:
          return c