code: def forward(
      self,
      body_features,
      proposal_bboxes,
      proposal_features,
      targets=None,
  ):
      if self.training:
          return self._forward_train(
              body_features, proposal_bboxes, proposal_features, targets
          )
      else:
          return self._forward_test(
              body_features, proposal_bboxes, proposal_features
          )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import copy
  import paddle
  from paddle import nn
  from ppdet.core.workspace import register
  from ppdet.modeling import initializer
  from .roi_extractor import RoIAlign
  from ..bbox_utils import delta2bbox_v2
  from ..cls_utils import _get_class_default_kwargs
  from ..layers import MultiHeadAttention
label_desc: Use image node_id 6 for calling the SparseRoIHead obj's underlying member method code with example usage: obj.forward(body_features, proposal_bboxes, proposal_features, targets) and returns: self, self