问题似乎与该模块位于父目录或类似内容无关.

It seems that the problem is not related to the module being in a parent directory or anything like that.

您需要将包含ptdraft的目录添加到PYTHONPATH

You need to add the directory that contains ptdraft to PYTHONPATH

您说import nib与您一起工作，这可能意味着您已将ptdraft本身(而不是其父项)添加到PYTHONPATH中.

You said that import nib worked with you, that probably means that you added ptdraft itself (not its parent) to PYTHONPATH.