new_contents: from problem0003 import primes
  from itertools import islice
  
  
  def nth(iterable, n):
      '''return n-th element from given iterable
      >>> nth([1, 2, 3, 4], 2)
      2
      '''
      return next(islice(iterable, n-1, None))
  
  if __name__ == '__main__':
      print(nth(primes(), 10001))
  
subject: add problem0007.py