input: Write a function to print the following pattern using nested loops: a series of asterisks increasing from 1 to 5, followed by decreasing back to 1. The function should take no input parameters and should print the pattern directly.
  assert print_pattern_function()
  assert print_pattern_function()
output: def print_pattern_function():
      for i in range(1, 6):
          print('*' * i)
      for i in range(4, 0, -1):
          print('*' * i)