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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_source(self, arg):
 """source expression Try to get source code for the given object and display it. """

        try:
            obj = self._getval(arg)
        except Exception:
            return
        try:
            lines, lineno = getsourcelines(obj, self.get_locals(self.curframe))
        except (IOError, TypeError) as err:
            self.error(err)
            return
        self._print_lines(lines, lineno)