[py]: set exception direct cause when switching frame focus when NSE is raised

Author: symonk

py/selenium/webdriver/remote/switch_to.py

@@ -89,8 +89,8 @@ def frame(self, frame_reference: Union[str, int, WebElement]) -> None:
             except NoSuchElementException:
                 try:
                     frame_reference = self._driver.find_element(By.NAME, frame_reference)
-                except NoSuchElementException:
-                    raise NoSuchFrameException(frame_reference)
+                except NoSuchElementException as exc:
+                    raise NoSuchFrameException(frame_reference) from exc
 
         self._driver.execute(Command.SWITCH_TO_FRAME, {"id": frame_reference})