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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 abort(self, err):
 """Called by a client to abort all of the member transactions. When the last pending member is aborted the group callback function will be called."""

        if _debug: IOGroup._debug("abort %r", err)

        # change the state to reflect that it was killed
        self.ioState = ABORTED
        self.ioError = err

        # abort all the members
        for iocb in self.ioMembers:
            iocb.abort(err)

        # notify the client
        self.trigger()