code: def provide_data(self):
      return [mx.io.DataDesc("data", self.data.shape, self.dtype)]
  
file_path: byteps/example/mxnet/common/data_byteps.py
imports: import mxnet
  import random
  from mxnet.io import DataBatch, DataIter
  import numpy
label_desc: Use image node_id 3 for calling the SyntheticDataIter obj's underlying member method code with example usage: obj.provide_data() and returns: list