code: def test_entropy(self):
      entropy = self.distrib.entropy
      for b in range(self.batch_size):
          cov = np.identity(self.ndim, dtype=np.float32) * self.var[b]
          desired_entropy = scipy.stats.multivariate_normal(
              self.mean[b], cov
          ).entropy()
          np.testing.assert_allclose(
              entropy.array[b], desired_entropy, rtol=1e-4
          )
  
imports: import unittest
  import chainer
  from chainer import testing
  from chainer.testing import condition
  import numpy
  import scipy.stats
  from chainerrl import distribution
label_desc: Use image node_id 7 for calling the TestGaussianDistribution obj's underlying member method code with example usage: obj.test_entropy() without return types