code: def execute(self, conn, site_name= "", transaction = False):
          
          sql = self.sql
          if site_name == "":
              result = self.dbi.processData(sql, conn=conn, transaction=transaction)
          else:
              sql += "WHERE S.SITE_NAME = :site_name" 
              binds = { "site_name" : site_name }
              result = self.dbi.processData(sql, binds, conn, transaction)
          return self.formatDict(result)
docs: Lists all sites types if site_name is not provided.