code: def _fake_enumerateclassnames(self, namespace, **params):
          
  
          self._validate_namespace(namespace)
  
          classname = params.get('ClassName', None)
          if classname:
              assert(isinstance(classname, CIMClassName))
              if not self._class_exists(classname.classname, namespace):
                  raise CIMError(
                      CIM_ERR_INVALID_CLASS,
                      _format("The class {0!A} defined by 'ClassName' parameter "
                              "does not exist in namespace {1!A}",
                              classname, namespace))
  
          clns = self._get_subclass_names(classname, namespace,
                                          params['DeepInheritance'])
          rtn_clns = [
              CIMClassName(cn, namespace=namespace, host=self.host)
              for cn in clns]
  
          return self._make_tuple(rtn_clns)
docs: Implements a mock server responder for
          :meth:`~pywbem.WBEMConnection.EnumerateClassNames`.
  
          Enumerates the classnames of the classname in the 'classname' parameter
          or from the top of the tree if 'classname is None.
  
          Returns:
  
              return tuple including list of classnames
  
          Raises:
  
              CIMError: CIM_ERR_INVALID_NAMESPACE: invalid namespace,
              CIMError: CIM_ERR_INVALID_CLASS: class defined by the classname
              parameter does not exist