def field_is_complex(self, field: ModelField) -> Tuple[bool, bool]:
        """
        Find out if a field is complex, and if so whether JSON errors should be ignored
        """
        if lenient_issubclass(field.annotation, JsonWrapper):
            return False, False

        if field.is_complex():
            allow_parse_failure = False
        elif is_union(get_origin(field.type_)) and field.sub_fields and any(f.is_complex() for f in field.sub_fields):
            allow_parse_failure = True
        else:
            return False, False

        return True, allow_parse_failure

        Find out if a field is complex, and if so whether JSON errors should be ignored
        
pydantic/v1/env_settings.py