class_docstr: Main model class.
code: def fit(self, *args, **kwargs):
      retval = super().fit(*args, **kwargs)
      # After training, fix range coding tables.
      self.entropy_model = tfc.LocationScaleIndexedEntropyModel(
          tfc.NoisyNormal,
          self.num_scales,
          self.scale_fn,
          coding_rank=3,
          compression=True,
      )
      self.side_entropy_model = tfc.ContinuousBatchedEntropyModel(
          self.hyperprior, coding_rank=3, compression=True
      )
      return retval
  
imports: import argparse
  import glob
  import sys
  from absl import app
  from absl.flags import argparse_flags
  import tensorflow
  import tensorflow_compression
  import tensorflow_datasets
label_desc: Use image node_id 7 for calling the BMSHJ2018Model obj's underlying member method code with example usage: obj.fit() and returns: retval