code: def testStdDev(self):
      for dt in get_float_types():
          stddev = 3.0
          sampler = self._Sampler(100000, 0.0, stddev, dt, use_gpu=True)
          x = sampler()
          print("std(x)", np.std(x), abs(np.std(x) / stddev - 0.85))
          self.assertLess(abs(np.std(x) / stddev - 0.85), 0.04)
  
imports: import numpy
  from tensorflow.python.eager import context
  from tensorflow.python.framework import config
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import random_seed
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import gen_random_ops
  from tensorflow.python.ops import random_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
label_desc: Use image node_id 5 for calling the TruncatedNormalTest obj's underlying member method code with example usage: obj.testStdDev() without return types