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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 readBytes(self, size):
 """ A read can block for an unbounded amount of time, even if the kernel reports that the pipe handle is signalled, so we need to always perform our reads asynchronously """


        # try to satisfy the read from any buffered data
        if self._iobuf:
            if size >= len(self._iobuf):
                res = self._iobuf
                self.buf = None
                return res
            res = self._iobuf[:size]
            self._iobuf = self._iobuf[size:]
            return res

        # We need to initiate a read
        buf = ctypes.create_string_buffer(size)
        olap = OVERLAPPED()
        olap.hEvent = self._waitable

        log("made read buff of size %d", size)

        # ReadFile docs warn against sending in the nread parameter for async
        # operations, so we always collect it via GetOverlappedResultEx
        immediate = ReadFile(self.pipe, buf, size, None, olap)

        if not immediate:
            err = GetLastError()
            if err != ERROR_IO_PENDING:
                self._raise_win_err("failed to read %d bytes" % size, err)

        nread = wintypes.DWORD()
        if not self._get_overlapped_result_ex(
            self.pipe, olap, nread, 0 if immediate else self.timeout, True
        ):
            err = GetLastError()
            CancelIoEx(self.pipe, olap)

            if err == WAIT_TIMEOUT:
                log("GetOverlappedResultEx timedout")
                raise SocketTimeout(
                    "timed out after waiting %dms for read" % self.timeout
                )

            log("GetOverlappedResultEx reports error %d", err)
            self._raise_win_err("error while waiting for read", err)

        nread = nread.value
        if nread == 0:
            # Docs say that named pipes return 0 byte when the other end did
            # a zero byte write.  Since we don't ever do that, the only
            # other way this shows up is if the client has gotten in a weird
            # state, so let's bail out
            CancelIoEx(self.pipe, olap)
            raise IOError("Async read yielded 0 bytes; unpossible!")

        # Holds precisely the bytes that we read from the prior request
        buf = buf[:nread]

        returned_size = min(nread, size)
        if returned_size == nread:
            return buf

        # keep any left-overs around for a later read to consume
        self._iobuf = buf[returned_size:]
        return buf[:returned_size]