fix except issue

page.py

@@ -37,7 +37,7 @@ class Page(object):
     def is_element_visible(self, *locator):
         try:
             return self.selenium.find_element(*locator).is_displayed()
-        except NoSuchElementException, ElementNotVisibleException:
+        except (NoSuchElementException, ElementNotVisibleException):
             return False
 
     def is_element_present(self, *locator):