coroutines

Thu Aug 3 03:53:43 EDT 2017

Hello
Here a code for a simple demultiplexer coroutine
def demultiplexer(target1, target2):
 while True:
 data = yield
 target1.send(data)
 target2.send(data)
When data is sent to target1, what Cpython do 
immediately after ?
1- Go on execute demultiplexer, so send a data 
to target2 then pause demultiplexer when it reach
line data=yied, then execute coroutine target1, then 
execute coroutine target2
or
2- Go and execute target1 coroutine, then resume 
demultiplexer, so send a data to target2, go to target2, 
then resume demultiplexer and stops