class_docstr: This class implements the `Feature Pyramid Network <https://arxiv.org/abs/1612.03144>`_ module for object detection.
  
  Args:
      opts: command-line arguments
      in_channels (List[int]): List of channels at different output strides
      output_strides (List[int]): Feature maps from these output strides will be used in FPN
      out_channels (int): Output channels
code: def __repr__(self):
      return "{}(in_channels={}, output_strides={} out_channels={})".format(
          self.__class__.__name__,
          self.in_channels,
          self.output_strides,
          self.out_channels,
      )
  
file_path: ml-cvnets/cvnets/modules/feature_pyramid.py
imports: from typing import Dict, List
  import torch
  import torch.nn.functional
  from torch import Tensor, nn
  from cvnets.layers import ConvLayer2d, norm_layers_tuple
  from cvnets.misc.init_utils import initialize_conv_layer, initialize_norm_layers
  from cvnets.modules import BaseModule
  from utils import logger
label_desc: Use image node_id 4 for calling the FeaturePyramidNetwork obj's underlying member method code with example usage: obj.__repr__() and returns: str