<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def bulk_launch(self, jobs=None, filter=None, all=False):
 # pylint: disable=redefined-builtin """Bulk launch a set of jobs. :param jobs: :class:`jobs.Job <jobs.Job>` list :param filter: (optional) Filters to apply as a string list. :param all: (optional) Apply to all if bool `True`. """

        json = None
        if jobs is not None:
            schema = JobSchema(exclude=('id', 'status', 'package_name', 'config_name', 'device_name', 'result_id', 'user_id', 'created', 'updated', 'automatic'))
            jobs_json = self.service.encode(schema, jobs, many=True)
            json = {self.RESOURCE: jobs_json}

        schema = JobSchema()
        resp = self.service.post(self.base,
                                 params={'bulk': 'launch', 'filter': filter, 'all': all}, json=json)
        return self.service.decode(schema, resp, many=True)