changed pycocotools.COCO to lowercose

[bvoq]

This had to be done for me to get the newest versions working. Maybe make sure it also works on your end this way?

[OpenMMLab-Coodinator]

Hi @bvoq ！We are grateful for your efforts in helping improve this open-source project during your personal time. Welcome to join OpenMMLab Special Interest Group (SIG) , where you can share your experiences, ideas, and build connections with like-minded peers.

To join the SIG channel, simply message moderator— OpenMMLab on Discord or briefly share your open-source contributions in the #introductions channel and we will assist you. Look forward to seeing you there! Join us ：https://discord.gg/UjgXkPWNqA

If you have a WeChat account，welcome to join our community on WeChat. You can add our assistant ：openmmlabwx. Please add "mmsig + Github ID" as a remark when adding friends：） Thank you again for your contribution❤