class_docstr: PanopticFPNHead used in Panoptic FPN.
  
  In this head, the number of output channels is ``num_stuff_classes
  + 1``, including all stuff classes and one thing class. The stuff
  classes will be reset from ``0`` to ``num_stuff_classes - 1``, the
  thing classes will be merged to ``num_stuff_classes``-th channel.
  
  Arg:
      num_things_classes (int): Number of thing classes. Default: 80.
      num_stuff_classes (int): Number of stuff classes. Default: 53.
      in_channels (int): Number of channels in the input feature
          map.
      inner_channels (int): Number of channels in inner features.
      start_level (int): The start level of the input features
          used in PanopticFPN.
      end_level (int): The end level of the used features, the
          ``end_level``-th layer will not be used.
      conv_cfg (Optional[Union[ConfigDict, dict]]): Dictionary to construct
          and config conv layer.
      norm_cfg (Union[ConfigDict, dict]): Dictionary to construct and config
          norm layer. Use ``GN`` by default.
      init_cfg (Optional[Union[ConfigDict, dict]]): Initialization config
          dict.
      loss_seg (Union[ConfigDict, dict]): the loss of the semantic head.
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docstr: Initialize weights.
docstr_tok: ["Initialize","weights","."]
code: def init_weights(self) -> None:
      """Initialize weights."""
      super().init_weights()
      nn.init.normal_(self.conv_logits.weight.data, 0, 0.01)
      self.conv_logits.bias.data.zero_()
  
file_path: mmdetection/mmdet/models/seg_heads/panoptic_fpn_head.py
imports: from typing import Dict, Tuple, Union
  import torch
  import torch.nn
  import torch.nn.functional
  from mmengine.model import ModuleList
  from torch import Tensor
  from mmdet.registry import MODELS
  from mmdet.structures import SampleList
  from mmdet.utils import ConfigType, OptConfigType, OptMultiConfig
  from ..layers import ConvUpsample
  from ..utils import interpolate_as
  from .base_semantic_head import BaseSemanticHead
label_desc: Use image node_id 4 for calling the PanopticFPNHead obj's underlying member method code with example usage: obj.init_weights() without return types