Updates job record property for a tree node associated with the given Job

def update_node(self, job_record):
        """ Updates job record property for a tree node associated with the given Job """
        if job_record.process_name not in self.process_hierarchy:
            raise ValueError('unable to update the node due to unknown process: {0}'.format(job_record.process_name))

        time_qualifier = self.process_hierarchy[job_record.process_name].process_entry.time_qualifier
        node = self._get_node(time_qualifier, job_record.timeperiod)
        node.job_record = job_record