'Return metadata for the file represented by stream (a file like object
that supports reading). Raise an exception when there is an error
with the input data.
:param type: The type of file. Guaranteed to be one of the entries
in :attr:`file_types`.
:return: A :class:`calibre.ebooks.metadata.book.Metadata` object'

def get_metadata(self, stream, type):

    return None
