Add a KE-chain Text widget to the customization.

        The widget will be saved to KE-chain.

        :param text: The text that will be shown by the widget.
        :type text: basestring or None
        :param custom_title: A custom title for the text panel::
            * None (default): No title
            * String value: Custom title
        :type custom_title: basestring or None
        :param collapsible: A boolean to decide whether the panel is collapsible or not (default True)
        :type collapsible: bool
        :param collapsed: A boolean to decide whether the panel is collapsed or not (default False)
        :type collapsible: bool
        :raises IllegalArgumentError: When unknown or illegal arguments are passed.

def add_text_widget(self, text=None, custom_title=None, collapsible=True, collapsed=False):
        """
        Add a KE-chain Text widget to the customization.

        The widget will be saved to KE-chain.

        :param text: The text that will be shown by the widget.
        :type text: basestring or None
        :param custom_title: A custom title for the text panel::
            * None (default): No title
            * String value: Custom title
        :type custom_title: basestring or None
        :param collapsible: A boolean to decide whether the panel is collapsible or not (default True)
        :type collapsible: bool
        :param collapsed: A boolean to decide whether the panel is collapsed or not (default False)
        :type collapsible: bool
        :raises IllegalArgumentError: When unknown or illegal arguments are passed.
        """
        # Declare text widget config
        config = {
            "xtype": ComponentXType.HTMLPANEL,
            "filter": {
                "activity_id": str(self.activity.id),
            }
        }

        # Add text and custom title
        if text:
            config['html'] = text
        if custom_title:
            show_title_value = "Custom title"
            title = custom_title
        else:
            show_title_value = "No title"
            title = None
        config['collapsible'] = collapsible
        # A widget can only be collapsed if it is collapsible in the first place
        if collapsible:
            config['collapsed'] = collapsed
        else:
            config['collapsed'] = False
        config['title'] = title
        # Declare the meta info for the property grid
        meta = {
            "activityId": str(self.activity.id),
            "customTitle": title,
            "collapsible": collapsible,
            "collapsed": collapsed,
            "html": text,
            "showTitleValue": show_title_value
        }

        self._add_widget(dict(config=config, meta=meta, name=WidgetNames.HTMLWIDGET))