泰坦尼克按性别舱位统计生存率

def solve():
    import sqlite3
    import pandas as pd
    conn = sqlite3.connect(':memory:')
    df = pd.read_csv('https://liangdaima.com/static/data/titanic.csv')
    df.to_sql('titanic', conn, index=False)
    result = conn.execute('SELECT sex, pclass, COUNT(*) AS total, SUM(CASE WHEN survived = 1 THEN 1 ELSE 0 END) AS survived, ROUND(100.0 * SUM(CASE WHEN survived = 1 THEN 1 ELSE 0 END) / COUNT(*), 2) AS survival_rate FROM titanic GROUP BY sex, pclass').fetchall()
    conn.close()
    return result