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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 add(self, iocb):
 """Add an IOCB to the group, you can also add other groups."""

        if _debug: IOGroup._debug("add %r", iocb)

        # add this to our members
        self.ioMembers.append(iocb)

        # assume all of our members have not completed yet
        self.ioState = PENDING
        self.ioComplete.clear()

        # when this completes, call back to the group.  If this
        # has already completed, it will trigger
        iocb.add_callback(self.group_callback)