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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 close(self, timeout=None):
 """Close this producer. Arguments: timeout (float, optional):
 timeout in seconds to wait for completion. """


        # drop our atexit handler now to avoid leaks
        self._unregister_cleanup()

        if not hasattr(self, '_closed') or self._closed:
            log.info('Kafka producer closed')
            return
        if timeout is None:
            # threading.TIMEOUT_MAX is available in Python3.3+
            timeout = getattr(threading, 'TIMEOUT_MAX', float('inf'))
        if getattr(threading, 'TIMEOUT_MAX', False):
            assert 0 <= timeout <= getattr(threading, 'TIMEOUT_MAX')
        else:
            assert timeout >= 0

        log.info("Closing the Kafka producer with %s secs timeout.", timeout)
        #first_exception = AtomicReference() # this will keep track of the first encountered exception
        invoked_from_callback = bool(threading.current_thread() is self._sender)
        if timeout > 0:
            if invoked_from_callback:
                log.warning("Overriding close timeout %s secs to 0 in order to"
                            " prevent useless blocking due to self-join. This"
                            " means you have incorrectly invoked close with a"
                            " non-zero timeout from the producer call-back.",
                            timeout)
            else:
                # Try to close gracefully.
                if self._sender is not None:
                    self._sender.initiate_close()
                    self._sender.join(timeout)

        if self._sender is not None and self._sender.is_alive():

            log.info("Proceeding to force close the producer since pending"
                     " requests could not be completed within timeout %s.",
                     timeout)
            self._sender.force_close()
            # Only join the sender thread when not calling from callback.
            if not invoked_from_callback:
                self._sender.join()

        self._metrics.close()
        try:
            self.config['key_serializer'].close()
        except AttributeError:
            pass
        try:
            self.config['value_serializer'].close()
        except AttributeError:
            pass
        self._closed = True
        log.debug("The Kafka producer has closed.")