code: def setUp(self):
      self.values = np.random.rand(self.batch_size, self.n)
      if self.wrap_by_variable:
          self.distrib = distribution.MellowmaxDistribution(
              chainer.Variable(self.values)
          )
      else:
          self.distrib = distribution.MellowmaxDistribution(self.values)
  
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 1 for calling the TestMellowmaxDistribution obj's underlying member method code with example usage: obj.setUp() without return types