Saves the actual file in the store.

           ``compress_hint`` suggests whether the file should be compressed
           before transfer

           Works like :meth:`add_stream`, but ``filename`` is the name of
           an existing file in the filesystem.

def add_file(self, name, filename, compress_hint=True):
        """Saves the actual file in the store.

           ``compress_hint`` suggests whether the file should be compressed
           before transfer

           Works like :meth:`add_stream`, but ``filename`` is the name of
           an existing file in the filesystem.
        """
        return self.add_stream(name, open(filename, 'rb'))