SelectorSocketTransport (in asyncio.selector_events) implements both write and writelines, but only the first has handling for the case that the connection has already been lost. That in turn can lead ...

print(f"Marks of student{i} in maths is:{m1}") print(f"Marks of student{i} in maths is:{m2}") print(f"Marks of student{i} in maths is:{m3}") ...