#!/usr/bin/env python3

class MyContainerType:
	def __init__(self, iterable):
		self._items = list(iterable)
	def __getitem__(self, index):
		return self._items[index] + 2
	def __setitem__(self, index, value):
		self._items[index] = value - 2
	def __len__(self):
		return len(self._items)
	def __iter__(self):
		for i in self._items:
			yield i + 2

foo = MyContainerType(range(10))
print(foo[3])
foo[3] = 99
print(*foo)
print(*foo._items)