code: def _unique_graph(fetches):
      graph = set([t.graph for t in fetches])
      assert len(graph) == 1, "there can only be one graph"
      return graph.pop()
  
imports: import tensorflow
  import numpy
  import logging
  import tempfile
  import pandas
  from pyspark import RDD, SparkContext
  from pyspark.sql import SQLContext, Row, DataFrame
  from pyspark.sql.types import DoubleType, IntegerType, LongType, FloatType, ArrayType
label_desc: Use image node_id 12 for calling a global function with example usage: _unique_graph(fetches) and returns: graph