How to use the apscheduler.util.datetime_to_utc_timestamp function in APScheduler

def add_job(self, job):
        try:
            self.collection.insert({
                '_id': job.id,
                'next_run_time': datetime_to_utc_timestamp(job.next_run_time),
                'job_state': Binary(pickle.dumps(job.__getstate__(), self.pickle_protocol))
            })
        except DuplicateKeyError:
            raise ConflictingIdError(job.id)

def add_job(self, job):
        if self.redis.hexists(self.jobs_key, job.id):
            raise ConflictingIdError(job.id)

        with self.redis.pipeline() as pipe:
            pipe.multi()
            pipe.hset(self.jobs_key, job.id, pickle.dumps(job.__getstate__(), self.pickle_protocol))
            pipe.zadd(self.run_times_key, datetime_to_utc_timestamp(job.next_run_time), job.id)
            pipe.execute()

def update_job(self, job):
        update = self.jobs_t.update().values(**{
            'next_run_time': datetime_to_utc_timestamp(job.next_run_time),
            'job_state': pickle.dumps(job.__getstate__(), self.pickle_protocol)
        }).where(self.jobs_t.c.id == job.id)
        result = self.engine.execute(update)
        if result.rowcount == 0:
            raise JobLookupError(job.id)

def add_job(self, job):
        self._ensure_paths()
        node_path = os.path.join(self.path,  str(job.id))
        value = {
            'next_run_time': datetime_to_utc_timestamp(job.next_run_time),
            'job_state': job.__getstate__()
        }
        data = pickle.dumps(value, self.pickle_protocol)
        try:
            self.client.create(node_path, value=data)
        except NodeExistsError:
            raise ConflictingIdError(job.id)

def get_due_jobs(self, now):
        timestamp = datetime_to_utc_timestamp(now)
        job_ids = self.redis.zrangebyscore(self.run_times_key, 0, timestamp)
        if job_ids:
            job_states = self.redis.hmget(self.jobs_key, *job_ids)
            return self._reconstitute_jobs(zip(job_ids, job_states))
        return []

def add_job(self, job):
        if self.redis.hexists(self.jobs_key, job.id):
            raise ConflictingIdError(job.id)

        with self.redis.pipeline() as pipe:
            pipe.multi()
            pipe.hset(self.jobs_key, job.id, pickle.dumps(job.__getstate__(),
                                                          self.pickle_protocol))
            if job.next_run_time:
                pipe.zadd(self.run_times_key,
                          {job.id: datetime_to_utc_timestamp(job.next_run_time)})

            pipe.execute()

def update_job(self, job):
        if not self.redis.hexists(self.jobs_key, job.id):
            raise JobLookupError(job.id)

        with self.redis.pipeline() as pipe:
            pipe.hset(self.jobs_key, job.id, pickle.dumps(job.__getstate__(), self.pickle_protocol))
            if job.next_run_time:
                pipe.zadd(self.run_times_key, datetime_to_utc_timestamp(job.next_run_time), job.id)
            else:
                pipe.zrem(self.run_times_key, job.id)
            pipe.execute()

def update_job(self, job):
        old_job, old_timestamp = self._jobs_index.get(job.id, (None, None))
        if old_job is None:
            raise JobLookupError(job.id)

        # If the next run time has not changed, simply replace the job in its present index.
        # Otherwise, reinsert the job to the list to preserve the ordering.
        old_index = self._get_job_index(old_timestamp, old_job.id)
        new_timestamp = datetime_to_utc_timestamp(job.next_run_time)
        if old_timestamp == new_timestamp:
            self._jobs[old_index] = (job, new_timestamp)
        else:
            del self._jobs[old_index]
            new_index = self._get_job_index(new_timestamp, job.id)
            self._jobs.insert(new_index, (job, new_timestamp))

        self._jobs_index[old_job.id] = (job, new_timestamp)

def get_due_jobs(self, now):
        timestamp = datetime_to_utc_timestamp(now)
        return self._get_jobs({'next_run_time': {'$lte': timestamp}})

def update_job(self, job):
        changes = {
            'next_run_time': datetime_to_utc_timestamp(job.next_run_time),
            'job_state': Binary(pickle.dumps(job.__getstate__(), self.pickle_protocol))
        }
        result = self.collection.update({'_id': job.id}, {'$set': changes})
        if result and result['n'] == 0:
            raise JobLookupError(job.id)