คู่ต่อสู้คนใดในรอบชิงชนะเลิศมีคู่หูของ Gastrnn Etlis?
What Opponent in the final had a Partner of Gastón Etlis?
df = pd.DataFrame(columns=['opponent_in_the_final', 'partner'])
df[df['partner'] == 'Gastón Etlis']['opponent_in_the_final']