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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 precmd(self, line):
 """This method is called after the line has been input but before it has been interpreted. If you want to modify the input line before execution (for example, variable substitution) do it here. """

        line = self.prefix + line
        self._history += [line.strip()]
        return line