#### 4.1.7 Notes

Warning: In order to avoid infinite recursion with the user conversion functions, the value functions in the `class_table` and the key and value functions in the `proc_table`, are evaluated in the `BASIC_CONVERSION` mode (see Basic conversion). This allows the R functions, called inside the conversion functions, to return Python values, without consulting the tables again. You may force other conversion modes with the `as_py()` method of the `Robj` type (see Methods of Robj type), but you should be careful.