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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 __pkg_upgrade_flags(self, flags):
 """Manage flags for package upgrade option """

        flag, skip = [], ""
        if flags[0] in self.args:
            for arg in self.args[3:]:
                if arg.startswith(flags[1]):
                    skip = Regex(arg.split("=")[1]).get()
                    self.args.remove(arg)
                if arg in flags:
                    flag.append(arg)
                    if arg in self.args:
                        self.args.remove(arg)
        return flag, skip