code: def setSpecialPrice(self, product, special_price=None,
                          from_date=None, to_date=None, store_view=None,
                          identifierType=None):
          
          return bool(self.call(
              'catalog_product.setSpecialPrice', [
                  product, special_price, from_date, to_date, store_view,
                  identifierType
              ]
          ))
docs: Update product's special price
  
          :param product: ID or SKU of product
          :param special_price: Special Price
          :param from_date: From date
          :param to_date: To Date
          :param store_view: ID or Code of Store View
          :param identifierType: Defines whether the product or SKU value is
                                 passed in the "product" parameter.
  
          :return: Boolean