def __init__(self, preprocessing_fn, pipeline=None):
    """Init method.

    Args:
      preprocessing_fn: A function that accepts and returns a dictionary from
        strings to `Tensor`s, `SparseTensor`s, or `RaggedTensor`s.
      pipeline: (Optional) a beam Pipeline.
    """
    self._preprocessing_fn = preprocessing_fn
    self.pipeline = pipeline
    self._save_options = Context.get_save_options()
    self._use_tf_compat_v1 = Context.get_use_tf_compat_v1()
    if self._use_tf_compat_v1:
      _warn_about_tf_compat_v1()
Init method.

    Args:
      preprocessing_fn: A function that accepts and returns a dictionary from
        strings to `Tensor`s, `SparseTensor`s, or `RaggedTensor`s.
      pipeline: (Optional) a beam Pipeline.
    
tensorflow_transform/beam/impl.py