[py] implement relative locator for find_element (#9902)

Co-authored-by: David Burns <[email protected]>

Author: titusfortner

py/selenium/webdriver/remote/webdriver.py

@@ -1220,6 +1220,9 @@ def find_element(self, by=By.ID, value=None) -> WebElement:
 
         :rtype: WebElement
         """
+        if isinstance(by, RelativeBy):
+            return self.find_elements(by=by, value=value)[0]
+
         if by == By.ID:
             by = By.CSS_SELECTOR
             value = '[id="%s"]' % value

py/test/selenium/webdriver/support/relative_by_tests.py

@@ -19,6 +19,15 @@
 from selenium.webdriver.support.relative_locator import with_tag_name, locate_with
 
 
+def test_should_be_able_to_find_first_one(driver, pages):
+    pages.load("relative_locators.html")
+    lowest = driver.find_element(By.ID, "below")
+
+    el = driver.find_element(with_tag_name("p").above(lowest))
+
+    assert el.get_attribute('id') == "mid"
+
+
 def test_should_be_able_to_find_elements_above_another(driver, pages):
     pages.load("relative_locators.html")
     lowest = driver.find_element(By.ID, "below")