code: def test_create_continuous_by_default(self):
      space = [{"domain": (-1, 1)}]
  
      design_space = Design_space(space)
  
      self.assertEqual(len(design_space.space_expanded), 1)
      self.assertIsInstance(
          design_space.space_expanded[0], ContinuousVariable
      )
  
imports: import numpy
  import unittest
  from GPyOpt.core.task.space import Design_space
  from GPyOpt.core.task.variables import BanditVariable, DiscreteVariable, CategoricalVariable, ContinuousVariable
  from GPyOpt.core.errors import InvalidConfigError
label_desc: Use image node_id 7 for calling the TestDesignSpace obj's underlying member method code with example usage: obj.test_create_continuous_by_default() without return types