计算不良贷款率NPL ratio

def solve():
    from pyodide.http import open_url
    clients_csv = open_url(____).read()
    loans_csv = open_url(____).read()
    loan_classifications_csv = open_url(____).read()
    loan_provisions_csv = open_url(____).read()
    import sqlite3, pandas as pd
    from io import StringIO
    conn = sqlite3.connect(____)
    pd.read_csv(StringIO(____)).to_sql(____)
    total = pd.read_sql_query(____).iloc[____]['____'] or ____
    npl = pd.read_sql_query(____).iloc[____]['____'] or ____
    npl_ratio = round(____) if total > ____ else ____
    print(____)
    print(____)
    print(____)
    print(____)
    conn.close()