Open a buttons link in a new tab [nodriver]

Hey, so I was able to extract the href of a button and im basically trying to open that link in a new tab. Im new to nodriver and cant really find anything where you can open the button in a new tab. I have this down right now, if someone could point me in the right direction, it would be really helpful.

 try:
     tab = await browser.get("https://www.website.com")
     await asyncio.sleep(3)

     sign_up_button = await tab.find("//a[@class='styles__ButtonRoot-sc-1ldytso-0 bzOPhu']")
     print(f"Sign Up Button: {sign_up_button}") # this prints the entire html for the button

     # Open the sign-up URL in a new tab
     sign_up_url = await sign_up_button.get_attribute("href") # most likely wrong
     print(f"Sign Up URL: {sign_up_url}") # does not print

     # Open the sign-up URL in a new tab
     signup_tab = await browser.get(sign_up_url)
     await asyncio.sleep(5)

the print of “Sign Up Button:” is displayed, shows the entire html for the button, including the href, but for some reason the bot stops there and cant grab the href and open it. Keep getting 'NoneType' object is not callable