code: def testSingletonDimension(self):
      input_arrays = [
          _input_array(num_dims=5).reshape(
              [2] * i + [1] + [2] * (5 - i)
          )
          for i in range(6)
      ]
      truth = _input_array(num_dims=5)
      truth_shape = [2] * 5
      for i in range(6):
          self._testReduceJoin(
              input_arrays[i], truth, truth_shape, axis=i
          )
  
imports: import itertools
  import numpy
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import string_ops
  from tensorflow.python.platform import test
label_desc: Use image node_id 7 for calling the ReduceJoinTest obj's underlying member method code with example usage: obj.testSingletonDimension() without return types