For convenience, this function may be called on a nano object as well
as a socket, in which case it is the equivalent of calling the function
on the object's socket directly.
Contexts allow the independent and concurrent use of stateful
operations using the same socket. For example, two different contexts
created on a rep socket can each receive requests, and send replies to
them, without any regard to or interference with each other.
Note: not every protocol supports creation of separate contexts.
To send and receive over a context use send_ctx
and
recv_ctx
respectively. It is also possible to perform async
send and receive over a context using send_aio
and
recv_aio
.