class_docstr: Add Suffix to src (& tgt) sentence.
docstr: Prepend `suffix` to `tokens`.
docstr_tok: ["Prepend","`","suffix","`","to","`","tokens","`","."]
code: def _append(self, example, suffix):
      """Prepend `suffix` to `tokens`."""
      for side, side_suffix in suffix.items():
          if example.get(side) is not None:
              example[side] = example[side] + side_suffix.split()
          elif len(side_suffix) > 0:
              example[side] = side_suffix.split()
      return example
  
imports: from onmt.utils.logging import logger
  from onmt.transforms import register_transform
  from .transform import Transform, ObservableStats
label_desc: Use image node_id 7 for calling the SuffixTransform obj's underlying member method code with example usage: obj._append(example, suffix) and returns: example