mmdetection/configs/faster_rcnn/faster-rcnn_r101_fpn_ms-3x_coco.py

_base_ = 'faster-rcnn_r50_fpn_ms-3x_coco.py'

model = dict(
    backbone=dict(
        depth=101,
        init_cfg=dict(type='Pretrained',
                      checkpoint='torchvision://resnet101')))