old_contents: # Chapter 16 Practice Questions
  
  # 1. Why can't a brute-force attack be used against a simple substitution
  # cipher, even with a powerful supercomputer?
  # Hint: Check page 208
  from math import factorial  # Don't do this - imports should be at the top of the file
  numKeys = factorial(26)
  print(numKeys)
  
  # 2. What does the spam variable contain after running this code?
  spam = [4, 6, 2, 8]
  spam.sort()
  print(spam)
  
  # 3. What is a wrapper function?
  # Hint: Check page 213
  
  
  def calculator(num1, num2, mode):
      if mode == "add":
          return num1 + num2
      elif mode == "subtract":
          return num1 - num2
      return None
  
  
  def addition(num1, num2):
      return calculator(num1, num2, "add")
  
  
  def subtraction(num1, num2):
      return calculator(num1, num2, "subtract")
  
  
  print(addition(3, 4))
  print(subtraction(2, 1))
  
  # 4. What does 'hello'.islower() evaluate to?
  print('hello'.islower())
  
  # 5. What does 'HELLO 123'.isupper() evaluate to?
  print('HELLO 123'.isupper())
  
  # 6. What does '123'.islower() evaluate to?
  print('123'.islower())
  
new_contents: # Chapter 16 Practice Questions
  
  # 1. Why can't a brute-force attack be used against a simple substitution
  # cipher, even with a powerful supercomputer?
  # Hint: Check page 208
  from math import factorial
  numKeys = factorial(26)
  print(numKeys)
  
  # 2. What does the spam variable contain after running this code?
  spam = [4, 6, 2, 8]
  spam.sort()
  print(spam)
  
  # 3. What is a wrapper function?
  # Hint: Check page 213
  
  
  def calculator(num1, num2, mode):
      if mode == "add":
          return num1 + num2
      elif mode == "subtract":
          return num1 - num2
      return None
  
  
  def addition(num1, num2):
      return calculator(num1, num2, "add")
  
  
  def subtraction(num1, num2):
      return calculator(num1, num2, "subtract")
  
  
  print(addition(3, 4))
  print(subtraction(2, 1))
  
  # 4. What does 'hello'.islower() evaluate to?
  print('hello'.islower())
  
  # 5. What does 'HELLO 123'.isupper() evaluate to?
  print('HELLO 123'.isupper())
  
  # 6. What does '123'.islower() evaluate to?
  print('123'.islower())
  
subject: Update Ch. 16 PracticeQuestions: removed comment