generaor_with_collector.py

In [1]: collector = {}

In [2]: def _generator(collector):
   ...:     for i in range(10):
   ...:         collector.add(i*2)
   ...:         yield i
   ...: 

In [3]: collector = set()

In [4]: gen = _generator(collector)

In [5]: list(gen)
Out[5]: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

In [6]: collector
Out[6]: {0, 2, 4, 6, 8, 10, 12, 14, 16, 18}