def build_header(self):
        "Build header from key and primer values in current use."
        header = '\n'.join(map(self.bytes_to_repr, self.key.data))
        header += '\n' + self.bytes_to_repr(self.primer.data)
        return header
Build header from key and primer values in current use.
recipes/Python/578076_Markov/recipe-578076.py