text: from models.datatable import Datatable
  
  class DatatableBrand(Datatable):
    def build_sql(self):
      sql = 'SELECT "Brand", COUNT("Receipt ID") AS "Sales", SUM("Quantity Sold") AS Units FROM "Sales_by_item" GROUP BY "Brand";'
      return sql
  
    def field_names(self):
      return ['brand', 'sales', 'units']
  