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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 removeJob(self, jobBatchSystemID):
 """Removes a job from the system."""

        assert jobBatchSystemID in self.jobBatchSystemIDToIssuedJob
        jobNode = self.jobBatchSystemIDToIssuedJob[jobBatchSystemID]
        if jobNode.preemptable:
            # len(jobBatchSystemIDToIssuedJob) should always be greater than or equal to preemptableJobsIssued,
            # so decrement this value before removing the job from the issuedJob map
            assert self.preemptableJobsIssued > 0
            self.preemptableJobsIssued -= 1
        del self.jobBatchSystemIDToIssuedJob[jobBatchSystemID]
        # If service job
        if jobNode.jobStoreID in self.toilState.serviceJobStoreIDToPredecessorJob:
            # Decrement the number of services
            if jobNode.preemptable:
                self.preemptableServiceJobsIssued -= 1
            else:
                self.serviceJobsIssued -= 1

        return jobNode