@abc.abstractmethod<EOL><INDENT>def is_read_only(self):<DEDENT>
return<EOL>
Tests if this data can be updated.

        This may indicate the result of a pre-authorization but is not a
        guarantee that an authorization failure will not occur when the
        create or update transaction is issued.

        :return: ``true`` if this data is not updatable, ``false`` otherwise
        :rtype: ``boolean``


        *compliance: mandatory -- This method must be implemented.*