input: 
  def print_stars_pattern():
      """Print a pattern of stars that first increases in size and then decreases.
      >>> print_stars_pattern()
      *
      **
      ***
      ****
      *****
      ****
      ***
      **
      *
      """
      for i in range(5):
          for j in range(i+1):
              print("*", end="")
          print("")
  
      for i in range(5, 0, -1):
          for j in range(i):
              print("*", end="")
          print("")
  
output:     for i in range(4, 0, -1):
          for j in range(i):
              print("*", end="")
          print("")