@classmethod<EOL><INDENT>def diff_safe(cls, value):<DEDENT>
if isinstance(value, Frame):<EOL><INDENT>return {'<STR_LIT>': str(value), '<STR_LIT>': value._id}<EOL><DEDENT>elif isinstance(value, (list, tuple)):<EOL><INDENT>return [cls.diff_safe(v) for v in value]<EOL><DEDENT>return value<EOL>
Return a value that can be safely stored as a diff