How to use the @remirror/react-utils.propIsFunction function in @remirror/react-utils

constructor(props: RemirrorProps, context: RemirrorThemeContextType) {
    super(props, context);

    // Ensure that children is a render prop.
    propIsFunction(props.children);

    // Initialize the manager and create the initial state.
    this.manager.init({
      getState: this.getState,
      getTheme: this.getTheme,
      portalContainer: this.portalContainer,
    });
    this.state = this.createInitialState();

    // Create the ProsemirrorView and initialize our extension manager with it.
    this.view = this.createView();
    this.manager.initView(this.view);
  }

public componentDidUpdate(
    { editable, manager: prevManager }: RemirrorProps,
    prevState: RemirrorState>,
  ) {
    // Ensure that children is still a render prop
    propIsFunction(this.props.children);

    // Check whether the editable prop has been updated
    if (this.props.editable !== editable && this.view && this.editorRef) {
      this.view.setProps({ ...this.view.props, editable: () => this.props.editable });
    }

    // Check if the manager has changed
    if (!prevManager.isEqual(this.props.manager)) {
      this.updateExtensionManager();
      this.view.setProps({ ...this.view.props, nodeViews: this.manager.data.nodeViews });

      // The following converts the current content to HTML and then uses the
      // new manager schema to convert it back into a ProsemirrorNode for
      // compatibility with the new manager.
      const htmlString = toHTML({ node: this.state.editor.newState.doc, schema: prevManager.schema });
      const newContent = fromHTML({ schema: this.manager.schema, content: htmlString, doc: this.doc });