code: def testCDFNoBatch(self):
      histogram = [0.1, 0.2, 0.3, 0.4]
      event = 2
      expected_cdf = 0.6
      dist = categorical.Categorical(
          probs=histogram, validate_args=True
      )
      cdf_op = dist.cdf(event)
  
      self.assertAlmostEqual(expected_cdf, self.evaluate(cdf_op))
  
imports: from absl.testing import parameterized
  import numpy
  import tensorflow.compat.v1
  import tensorflow.compat.v2
  from tensorflow_probability.python.bijectors import identity
  from tensorflow_probability.python.distributions import categorical
  from tensorflow_probability.python.distributions import kullback_leibler
  from tensorflow_probability.python.distributions import normal
  from tensorflow_probability.python.internal import prefer_static
  from tensorflow_probability.python.internal import tensorshape_util
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math import gradient
  from tensorflow_probability.python.util import deferred_tensor
label_desc: Use image node_id 12 for calling the CategoricalTest obj's underlying member method code with example usage: obj.testCDFNoBatch() without return types