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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 load_preseed():
 """ Update JobPriority information from preseed.json The preseed data has these fields: buildtype, testtype, platform, priority, expiration_date The expiration_date field defaults to 2 weeks when inserted in the table The expiration_date field has the format "YYYY-MM-DD", however, it can have "*" to indicate to never expire The default priority is 1, however, if we want to force coalescing we can do that The fields buildtype, testtype and platform can have * which makes ut match all flavors of the * field. For example: (linux64, pgo, *) matches all Linux 64 pgo tests """


    if not JobPriority.objects.exists():
        return
    preseed = preseed_data()
    for job in preseed:
        queryset = JobPriority.objects.all()

        for field in ('testtype', 'buildtype', 'platform'):
            if job[field] != '*':
                queryset = queryset.filter(**{field: job[field]})

        # Deal with the case where we have a new entry in preseed
        if not queryset:
            create_new_entry(job)
        else:
            # We can have wildcards, so loop on all returned values in data
            for jp in queryset:
                process_job_priority(jp, job)