The documentation [1] for Coroutine in typing library writes:

class typing.Coroutine(Awaitable[V_co], Generic[T_co T_contra, V_co])

which should be:

class typing.Coroutine(Awaitable[V_co], Generic[T_co, T_contra, V_co])

a comma is missed between the first type variable T_co and the second one T_contr.

[1] https://docs.python.org/3/library/typing.html#typing.Generic