@property<EOL><INDENT>def value(self):<DEDENT>
result = self._value<EOL>if result is None and self._svalue is not None:<EOL><INDENT>try:<EOL><INDENT>result = self._value = self.resolve()<EOL><DEDENT>except Exception as e:<EOL><INDENT>reraise(<EOL>Parameter.Error,<EOL>Parameter.Error('<STR_LIT>')<EOL>)<EOL><DEDENT><DEDENT>return result<EOL>
Get parameter value.

        If this cached value is None and this serialized value is not None,
        calculate the new value from the serialized one.

        :return: parameter value.
        :raises: TypeError if serialized value is not an instance of self ptype
            . ParserError if parsing step raised an error.