class_docstr: A layer that produces dense `Tensors` from context and example features.
code: def context_feature_columns(self):
      return self._context_feature_columns
  
imports: import six
  import tensorflow.compat.v2
  from tensorflow.python.feature_column import feature_column_lib
  from tensorflow_ranking.python import utils
label_desc: Use image node_id 2 for calling the EncodeListwiseFeatures obj's underlying member method code with example usage: obj.context_feature_columns() and returns: self