Macro create_exception_type_object 

#[doc(hidden)]
macro_rules! create_exception_type_object {
    ($module: expr, $name: ident, $base: ty, None) => { ... };
    ($module: expr, $name: ident, $base: ty, Some($doc: expr)) => { ... };
    ($module: expr, $name: ident, $base: ty, $doc: expr) => { ... };
}

impl PyTypeInfo for $name where $name is an exception newly defined in Rust code.