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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _handle_socket(self, event: int, fd: int, multi: Any, data: bytes) -> None: """Called by libcurl when it wants to change the file descriptors it cares about. """

        event_map = {
            pycurl.POLL_NONE: ioloop.IOLoop.NONE,
            pycurl.POLL_IN: ioloop.IOLoop.READ,
            pycurl.POLL_OUT: ioloop.IOLoop.WRITE,
            pycurl.POLL_INOUT: ioloop.IOLoop.READ | ioloop.IOLoop.WRITE,
        }
        if event == pycurl.POLL_REMOVE:
            if fd in self._fds:
                self.io_loop.remove_handler(fd)
                del self._fds[fd]
        else:
            ioloop_event = event_map[event]
            # libcurl sometimes closes a socket and then opens a new
            # one using the same FD without giving us a POLL_NONE in
            # between.  This is a problem with the epoll IOLoop,
            # because the kernel can tell when a socket is closed and
            # removes it from the epoll automatically, causing future
            # update_handler calls to fail.  Since we can't tell when
            # this has happened, always use remove and re-add
            # instead of update.
            if fd in self._fds:
                self.io_loop.remove_handler(fd)
            self.io_loop.add_handler(fd, self._handle_events, ioloop_event)
            self._fds[fd] = ioloop_event