Extensibility | Playwright Python

tag_selector = """
    // Must evaluate to a selector engine instance.
    {
      // Returns the first element matching given selector in the root's subtree.
      query(root, selector) {
        return root.querySelector(selector);
      },
      // Returns all elements matching given selector in the root's subtree.
      queryAll(root, selector) {
        return Array.from(root.querySelectorAll(selector));
      }
    }"""
# register the engine. selectors will be prefixed with "tag=".
playwright.selectors.register("tag", tag_selector)
# now we can use "tag=" selectors.
button = page.locator("tag=button")
button.click()
# we can combine it with built-in locators.
page.locator("tag=div").get_by_text("click me").click()
# we can use it in any methods supporting selectors.
button_count = page.locator("tag=button").count()