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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 cmdloop(self, intro=None):
 """A Cmd.cmdloop implementation"""

    style = style_from_pygments(BasicStyle, style_dict)
    self.preloop()
    stop = None
    while not stop:
        line = prompt(get_prompt_tokens=get_prompt_tokens, lexer=lexer,
                      get_bottom_toolbar_tokens=get_bottom_toolbar_tokens,
                      history=history, style=style, true_color=True,
                      on_exit='return-none', on_abort='return-none',
                      completer=QCompleter())
        if line is None or line.strip() == r'\\':
            raise SystemExit
        else:
            line = self.precmd(line)
            stop = self.onecmd(line)
        stop = self.postcmd(stop, line)
    self.postloop()