docs: def CLASSDEF(self, node):
          """Check names used in a class definition, including its decorators,
          base classes, and the body of its definition.
  
          Additionally, add its name to the current scope.
  
          """
          for deco in node.decorator_list:
              self.handleNode(deco, node)
          for baseNode in node.bases:
              self.handleNode(baseNode, node)
          if not PY2:
              for keywordNode in node.keywords:
                  self.handleNode(keywordNode, node)
          self.push_scope(ClassScope)
          if self.settings.get('run_doctests', False):
              self.defer_function(lambda: self.handle_doctests(node))
          for stmt in node.body:
              self.handleNode(stmt, node)
          self.pop_scope()
          self.add_binding(node, ClassDefinition(node.name, node))