I would prefer to add something to get the type without SOCK_NONBLOCK nor
SOCK_CLOEXEC. So new feature can only be added to Python 3.5. For older
Python versions, you can to filter manually, which is difficult because you
have yo check if SOCK_NONBLOCK and/or SOCK_CLOEXEC are available. You have
the same issue in the C language.

Anyway, all sockets are now created with SOCK_CLOEXEC since Python 3.4
because of the PEP 446 (cloexec).

We can add a new .sock_type attribute. Or .type could be an object with
attributes like: type (int/enum), cloexec, nonblock, etc.

Or simply a short helper method can be added. Ex:
socket.get_socket_type(sock) or socket.get_socket_type(sock.type).