mmdetection/configs/res2net/cascade-mask-rcnn_res2net-101_fpn_20e_coco.py

_base_ = '../cascade_rcnn/cascade-mask-rcnn_r50_fpn_20e_coco.py'
model = dict(
    backbone=dict(
        type='Res2Net',
        depth=101,
        scales=4,
        base_width=26,
        init_cfg=dict(
            type='Pretrained',
            checkpoint='open-mmlab://res2net101_v1d_26w_4s')))