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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 do_pp(self, arg):
 """pp expression Pretty-print the value of the expression. """

        obj = self._getval(arg)
        try:
            repr(obj)
        except Exception:
            self.message(bdb.safe_repr(obj))
        else:
            self.message(pprint.pformat(obj))