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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 tab_complete(self):

 """
 If there is a single option available one tab completes the option.
 """

        opts = self._complete_options()
        if len(opts) == 1:
            self.set_current_text(opts[0] + os.sep)
            self.hide_completer()