code: def list(self, *args, **kwargs):
          
          if kwargs.pop('force', None):
              headers = kwargs.get('headers', args[4] if len(args) > 4 else None) or dict()
              headers['force'] = True
              kwargs['headers'] = headers
  
              for key in super(Bucket, self).list(*args, **kwargs):
                  yield key
  
          else:
              prefix = kwargs.get('prefix', args[0] if args else '')
  
              for key in mimicdb.backend.smembers(tpl.bucket % self.name):
                  if key.startswith(prefix):
                      k = Key(self, key)
  
                      meta = mimicdb.backend.hgetall(tpl.key % (self.name, key))
  
                      if meta:
                          k._load_meta(meta['size'], meta['md5'])
  
                      yield k
docs: Return an iterable of keys from MimicDB.
  
          :param boolean force: If true, API call is forced to S3