code: def forward(self, inputs, device):
      (x,) = inputs
      ret = functions.split_axis(
          x, 1, self.axis, force_tuple=self.force_tuple
      )
      if self.force_tuple:
          assert isinstance(ret, tuple)
          assert len(ret) == 1
          return ret
      else:
          assert isinstance(ret, chainer.Variable)
          return (ret,)
  
imports: import unittest
  import numpy
  import six
  import chainer
  from chainer import functions
  from chainer import testing
  from chainer.testing import backend
label_desc: Use image node_id 2 for calling the TestSplitAxisForceArray obj's underlying member method code with example usage: obj.forward(inputs, device) and returns: ret, ret