class S3File(str):
    def __new__(cls, value, **kwds):
        return super(S3File, cls).__new__(cls, value)

    def __init__(self, value, **kwds):
        kwds["data"] = value
        self.kwds = kwds

    def put_into(self, bucket, key):
        return bucket.put(key, **self.kwds)
