Why are there many instances of using from fsdet import ... in the code instead of leveraging the equivalent definitions within iFS-RCNN?

[lxp-2003-12-01]

Hello respected author,

I noticed that in many parts of the code, components from the fsdet library are imported, such as in train_net.py:
from fsdet.config import get_cfg, set_global_cfg
from fsdet.engine import DefaultTrainer, default_argument_parser, default_setup
from fsdet.evaluation import (
COCOEvaluator, DatasetEvaluators, LVISEvaluator, PascalVOCDetectionEvaluator, verify_results
)

However, equivalent definitions for these components also exist within the iFS-RCNN codebase. Should I replace all imports from fsdet with the corresponding implementations from iFS-RCNN? I am confused about why the iFS-RCNN code defines these modules but does not use them directly. Could you kindly explain the rationale behind this design choice? Thank you very much for your time and guidance.