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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 register_sub(self, o):
 """Register argument a suboption for `self`."""


        if o.subopt in self.subopt_map:
            raise OptionConflictError(
              "conflicting suboption handlers for `%s'" % o.subopt,
              o)
        self.subopt_map[o.subopt] = o