OSError: [Errno 22] Invalid argument when using blend2bam under win10

[qingyao-code]

My panda3d-blend2bam version number is 0.21. Python is the version I installed on my local system, version 3.7.4. When I used blend2bam to convert blend, I made a mistake and tried it many times, which seemed to be caused by incorrect path splicing within blend2bam. The error is as follows：