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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 _key_tab(self):

 """Action for TAB key"""

        if self.is_cursor_on_last_line():
            empty_line = not self.get_current_line_to_cursor().strip()
            if empty_line:
                self.stdkey_tab()
            else:
                self.show_code_completion()