old_contents: """Power Digit Sum
  
  2^15 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26.
  
  What is the sum of the digits of the number 21000?
  """
  assert sum(int(x) for x in str(2 ** 1000)) == 1366
  
  
new_contents: """Power Digit Sum
  
  2^15 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26.
  
  What is the sum of the digits of the number 21000?
  """
  assert sum(int(x) for x in str(2 ** 1000)) == 1366
  
subject: Remove redundant empty line at end of file