计算某贷款账户当前未还本金余额

def solve():
    from pyodide.http import open_url
    clients_csv = open_url(____).read()
    loans_csv = open_url(____).read()
    loan_repayment_schedule_csv = open_url(____).read()
    loan_transactions_csv = open_url(____).read()
    loan_charges_csv = open_url(____).read()
    import sqlite3, pandas as pd
    from io import StringIO
    conn = sqlite3.connect(____)
    pd.read_csv(StringIO(____)).to_sql(____)
    pd.read_csv(StringIO(____)).to_sql(____)
    loan = pd.read_sql_query(____).iloc[____]
    repaid = pd.read_sql_query(____).iloc[____]['____']
    calc_balance = float(____) - float(____)
    consistent = abs(calc_balance - float(____)) < ____
    print(____)
    print(____)
    print(____)
    print(____)
    print(____)
    print(____)
    conn.close()