input: 
  def print_pattern():
      """ Print a pattern of '*' characters as follows:
      in the first section, print a right-angled triangle with increasing rows,
      and in the second section, print the same pattern in decreasing order.
      
      >>> print_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(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("")