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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 get_max(qs, field):
 """ get max for queryset. qs: queryset field: The field name to max. """

    max_field = '%s__max' % field
    num = qs.aggregate(Max(field))[max_field]
    return num if num else 0