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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_widgets(self):
 """Set widgets on the extra keywords tab."""

        self.clear()
        self.description_label.setText(
            'In this step you can set some extra keywords for the layer. This '
            'keywords can be used for creating richer reporting or map.')
        subcategory = self.parent.step_kw_subcategory.selected_subcategory()
        extra_keywords = subcategory.get('extra_keywords')
        for extra_keyword in extra_keywords:
            check_box, input_widget = extra_keywords_to_widgets(extra_keyword)
            self.widgets_dict[extra_keyword['key']] = [
                check_box,
                input_widget,
                extra_keyword
            ]

        # Add to layout
        index = 0
        for key, widgets in list(self.widgets_dict.items()):
            self.extra_keywords_layout.addWidget(widgets[0], index, 0)
            self.extra_keywords_layout.addWidget(widgets[1], index, 1)
            index += 1

        self.set_existing_extra_keywords()