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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 Define_TreeTable(self, heads, heads2=None):
        ''' Define a TreeTable with a heading row
            and optionally a second heading row.
        '''
        display_heads = []
        display_heads.append(tuple(heads[2:]))
        self.tree_table = TreeTable()
        self.tree_table.append_from_list(display_heads, fill_title=True)
        if heads2 is not None:
            heads2_color = heads2[1]
            row_widget = gui.TableRow()
            for index, field in enumerate(heads2[2:]):
                row_item = gui.TableItem(text=field,
                                         style={'background-color': heads2_color})
                row_widget.append(row_item, field)
            self.tree_table.append(row_widget, heads2[0])
        self.wid.append(self.tree_table)