class_docstr: Base test class for Optimisers on Cartesian Product Spaces. 
docstr: Child set up. 
docstr_tok: ["Child","set","up","."]
code: def _child_set_up(self):
      """Child set up."""
      pass
  
imports: import os
  import unittest
label_desc: Use image node_id 2 for calling the CPOptimiserBaseTestCase obj's underlying member method code with example usage: obj._child_set_up() without return types