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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 filter(self, track=None, follow=None, locations=None, event=None, record_keepalive=False):
 """ Returns an iterator for tweets that match a given filter track from the livestream of tweets happening right now. If a threading.Event is provided for event and the event is set, the filter will be interrupted. """

        if locations is not None:
            if type(locations) == list:
                locations = ','.join(locations)
            locations = locations.replace('\\', '')

        url = 'https://stream.twitter.com/1.1/statuses/filter.json'
        params = {
            "stall_warning": True,
            "include_ext_alt_text": True
        }
        if track:
            params["track"] = track
        if follow:
            params["follow"] = follow
        if locations:
            params["locations"] = locations
        headers = {'accept-encoding': 'deflate, gzip'}
        errors = 0
        while True:
            try:
                log.info("connecting to filter stream for %s", params)
                resp = self.post(url, params, headers=headers, stream=True)
                errors = 0
                for line in resp.iter_lines(chunk_size=1024):
                    if event and event.is_set():
                        log.info("stopping filter")
                        # Explicitly close response
                        resp.close()
                        return
                    if not line:
                        log.info("keep-alive")
                        if record_keepalive:
                            yield "keep-alive"
                        continue
                    try:
                        yield json.loads(line.decode())
                    except Exception as e:
                        log.error("json parse error: %s - %s", e, line)
            except requests.exceptions.HTTPError as e:
                errors += 1
                log.error("caught http error %s on %s try", e, errors)
                if self.http_errors and errors == self.http_errors:
                    log.warning("too many errors")
                    raise e
                if e.response.status_code == 420:
                    if interruptible_sleep(errors * 60, event):
                        log.info("stopping filter")
                        return
                else:
                    if interruptible_sleep(errors * 5, event):
                        log.info("stopping filter")
                        return
            except Exception as e:
                errors += 1
                log.error("caught exception %s on %s try", e, errors)
                if self.http_errors and errors == self.http_errors:
                    log.warning("too many exceptions")
                    raise e
                log.error(e)
                if interruptible_sleep(errors, event):
                    log.info("stopping filter")
                    return