text: _base_ = [
      '../_base_/models/retinanet_r50_fpn.py',
      '../_base_/datasets/coco_detection.py',
      '../_base_/schedules/schedule_1x.py', '../_base_/default_runtime.py'
  ]
  model = dict(
      backbone=dict(
          frozen_stages=1,
          norm_cfg=dict(type='SyncBN', requires_grad=True))
      )
  optimizer = dict(type='SGD', lr=0.01, momentum=0.9, weight_decay=0.0001)
  