docstr: Feed the `callback_out` data obtained from source to the ExternalSource nodes
  in the `pipeline`
docstr_tok: ["Feed","the","`","callback_out","`","data","obtained","from","source","to","the","ExternalSource","nodes","in","the","`","pipeline","`"]
code: def feed(self, pipeline, callback_out, batch_size):
      """Feed the `callback_out` data obtained from source to the ExternalSource nodes
      in the `pipeline`"""
      if self.is_multioutput:
          for op in self.utilized_instances:
              if self.batch:
                  data = callback_out[op._output_index]
              else:
                  # extract a single output
                  data = [
                      callback_out[i][op._output_index]
                      for i in range(batch_size)
                  ]
              pipeline._feed_input(
                  op._name,
                  data,
                  op._layout,
                  self._cuda_stream,
                  self.use_copy_kernel,
              )
      else:
          data = callback_out
          op = self.utilized_instances[0]
          pipeline._feed_input(
              op._name,
              data,
              op._layout,
              self._cuda_stream,
              self.use_copy_kernel,
          )
  
imports: from nvidia.dali import backend
  from nvidia.dali import tensors
  from nvidia.dali import types
  from nvidia.dali._multiproc.messages import TaskArgs, SampleRange
  import nvidia.dali.types
  from nvidia.dali._utils.external_source_impl import get_callback_from_source, accepted_arg_count, SourceKind
label_desc: Use image node_id 10 for calling the _ExternalSourceGroup obj's underlying member method code with example usage: obj.feed(pipeline, callback_out, batch_size) without return types