code: def create(cls, mr_spec, shard_number, shard_attempt, _writer_state=None):
      
      mapper_spec = mr_spec.mapper
      params = output_writers._get_params(mapper_spec)
      bucket_name = params.get(cls.BUCKET_NAME_PARAM)
      shards = mapper_spec.shard_count
  
      filehandles = []
      filename = (mr_spec.name + "/" + mr_spec.mapreduce_id +
                  "/shard-" + str(shard_number) + "-bucket-")
      for i in range(shards):
        full_filename = "/%s/%s%d" % (bucket_name, filename, i)
        filehandles.append(cloudstorage.open(full_filename, mode="w"))
      return cls(filehandles)
docs: Inherit docs.