Support for Buffered Datagram Protocols and Buffered Subprocess Protocol

Ideas
1

The BufferedProtocol for TCP has been implemented since Python 3.7.

class BufferedProtocol(BaseProtocol):
    __slots__ = ()

    def get_buffer(self, sizehint):
        pass

    def buffer_updated(self, nbytes):
        pass

    def eof_received(self):
        pass

Likewise, considering Python supports socket.recvfrom_into for UDP and readinto for sys.stdin.buffer, is it feasible to add support for “Buffered Datagram Protocols” and “Buffered Subprocess Protocol”?

class BufferedDatagramProtocol(BaseProtocol):
	__slots__ = ()

    def get_buffer(self, sizehint):
        pass

    def buffer_updated(self, nbytes, addr):
        pass

    def error_received(self, exc):
		pass

class BufferedSubprocessProtocol(BaseProtocol):
    __slots__ = ()

    def get_buffer(self, sizehint):
        pass

    def buffer_updated(self, fd, nbytes):
		pass

    def pipe_connection_lost(self, fd, exc):
        pass

    def process_exited(self):
        pass

Therefore, unnecessary data copies and memory allocation might be avoided, thereby resulting in noticeable performance improvement.