#!/usr/bin/env python3

class Obj():
  def __init__(self, word):
    self.word = word

  def __iter__(self):
    return Iterator(self.word)

class Iterator:
  def __init__(self, word):
    self.word = word
    self.index = 0

  def __next__(self):
    try:
      letter = self.word[self.index]
      self.index += 1
      return letter  
    except IndexError:
      raise StopIteration()    

  def __iter__(self):
    return self
    

obj = Obj('sergey')
it = iter(obj)

print(next(it))
print(next(it))
print(next(it))
print(next(it))
print(next(it))
print(next(it))