code: def isLoadedDF(df):
      """Returns True if the input DataFrame was produced by the loadTFRecords() method.
  
      This is primarily used by the Spark ML Pipelines APIs.
  
      Args:
        :df: Spark Dataframe
      """
      return df in loadedDF
  
file_path: TensorFlowOnSpark/tensorflowonspark/dfutil.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import nested_scopes
  from __future__ import print_function
  import tensorflow
  from pyspark.sql import Row
  from pyspark.sql.types import ArrayType, BinaryType, DoubleType, LongType, StringType, StructField, StructType
label_desc: Use image node_id 1 for calling a global function with example usage: isLoadedDF(df) and returns: unknown