old_contents: from huey.api import Huey, crontab
  try:
      import redis
      from huey.backends.redis_backend import RedisBlockingQueue
      from huey.backends.redis_backend import RedisDataStore
      from huey.backends.redis_backend import RedisEventEmitter
      from huey.backends.redis_backend import RedisSchedule
  
      class RedisHuey(Huey):
          def __init__(self, name='huey', store_none=False, always_eager=False,
                       **conn_kwargs):
              queue = RedisBlockingQueue(name, **conn_kwargs)
              result_store = RedisDataStore(name, **conn_kwargs)
              schedule = RedisSchedule(name, **conn_kwargs)
              events = RedisEventEmitter(name, **conn_kwargs)
              super(RedisHuey, self).__init__(
                  queue=queue,
                  result_store=result_store,
                  schedule=schedule,
                  events=events,
                  store_none=store_none,
                  always_eager=always_eager)
  
  except ImportError:
      class RedisHuey(object):
          def __init__(self, *args, **kwargs):
              raise RuntimeError('Error, "redis" is not installed. Install '
                                 'using pip: "pip install redis"')
  
  
  from huey.backends.sqlite_backend import SqliteBlockingQueue
  from huey.backends.sqlite_backend import SqliteDataStore
  from huey.backends.sqlite_backend import SqliteEventEmitter
  from huey.backends.sqlite_backend import SqliteSchedule
  
  
  class SqliteHuey(Huey):
      def __init__(self, name='huey', store_none=False, always_eager=False,
                   location=':memory:'):
          queue = SqliteBlockingQueue(name, location)
          result_store = SqliteDataStore(name, location)
          schedule = SqliteSchedule(name, location)
          events = SqliteEventEmitter(name, location=location)
          super(SqliteHuey, self).__init__(
              queue=queue,
              result_store=result_store,
              schedule=schedule,
              events=events,
              store_none=store_none,
              always_eager=always_eager)
  
new_contents: from huey.api import Huey, crontab
  try:
      import redis
      from huey.backends.redis_backend import RedisBlockingQueue
      from huey.backends.redis_backend import RedisDataStore
      from huey.backends.redis_backend import RedisEventEmitter
      from huey.backends.redis_backend import RedisSchedule
  
      class RedisHuey(Huey):
          def __init__(self, name='huey', store_none=False, always_eager=False,
                       **conn_kwargs):
              queue = RedisBlockingQueue(name, **conn_kwargs)
              result_store = RedisDataStore(name, **conn_kwargs)
              schedule = RedisSchedule(name, **conn_kwargs)
              events = RedisEventEmitter(name, **conn_kwargs)
              super(RedisHuey, self).__init__(
                  queue=queue,
                  result_store=result_store,
                  schedule=schedule,
                  events=events,
                  store_none=store_none,
                  always_eager=always_eager)
  
  except ImportError:
      class RedisHuey(object):
          def __init__(self, *args, **kwargs):
              raise RuntimeError('Error, "redis" is not installed. Install '
                                 'using pip: "pip install redis"')
  
  
  from huey.backends.sqlite_backend import SqliteBlockingQueue
  from huey.backends.sqlite_backend import SqliteDataStore
  from huey.backends.sqlite_backend import SqliteEventEmitter
  from huey.backends.sqlite_backend import SqliteSchedule
  
  
  class SqliteHuey(Huey):
      def __init__(self, name='huey', store_none=False, always_eager=False,
                   location=None):
          if location is None:
              raise ValueError("Please specify a database file with the "
                               "'location' parameter")
          queue = SqliteBlockingQueue(name, location)
          result_store = SqliteDataStore(name, location)
          schedule = SqliteSchedule(name, location)
          events = SqliteEventEmitter(name, location=location)
          super(SqliteHuey, self).__init__(
              queue=queue,
              result_store=result_store,
              schedule=schedule,
              events=events,
              store_none=store_none,
              always_eager=always_eager)
  
subject: Make 'location' parameter mandatory in SqliteHuey