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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_rmpostfix(self, arg):
 """Removes a postfix function from a variable. See 'postfix'."""

        altered = False
        if arg in self.curargs["functions"]:
            del self.curargs["functions"][arg]
            altered = True
        elif arg == "*":
            for varname in list(self.curargs["functions"].keys()):
                del self.curargs["functions"][varname]
            altered = True
        if altered:
            self.do_postfix("list")