// lesson: channels

Channels

Python has no built-in channel type, but queue.Queue plays the same role: one thread puts values in, another gets them out, and the queue itself handles the locking. A None put onto the queue is a common convention for "no more values" — a sentinel value the receiving side treats as a close signal, rather than real data.

import queue
import threading

q = queue.Queue()
threading.Thread(target=lambda: q.put(42)).start()
print(q.get())  # 42

› Fan In

15 pts

Implement merge(a, b) where a and b are queue.Queue instances that will each eventually receive a None sentinel marking end-of-stream. Return a new queue.Queue that yields every value from both inputs (order between them doesn't matter) and then yields None once both are exhausted.

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