text: _base_ = [
      '../_base_/models/retinanet_r50_fpn.py',
      '../_base_/datasets/coco_detection.py',
      '../_base_/schedules/schedule_1x.py',
      '../_base_/default_runtime.py'
  ]
  # optimizer
  model = dict(
      # pretrained='pretrained/pvt_v2_b0.pth',
      pretrained='https://github.com/whai362/PVT/releases/download/v2/pvt_v2_b0.pth',
      backbone=dict(
          type='pvt_v2_b0',
          style='pytorch'),
      neck=dict(
          type='FPN',
          in_channels=[32, 64, 160, 256],
          out_channels=256,
          start_level=1,
          add_extra_convs='on_input',
          num_outs=5))
  # optimizer
  optimizer = dict(_delete_=True, type='AdamW', lr=0.0001, weight_decay=0.0001)
  optimizer_config = dict(grad_clip=None)
  work_dir = 'work_dirs/coco/pvt_v2/retinanet_pvt_v2_b0_fpn_1x_coco'