生成月度存款变化分析（各月净流入）

def solve():
    from pyodide.http import open_url
    offices_csv = open_url("https://data.zuihe.com/dbd/core/state_08/offices.csv").read()
    staff_csv = open_url("https://data.zuihe.com/dbd/core/state_08/staff.csv").read()
    savings_products_csv = open_url("https://data.zuihe.com/dbd/core/state_08/savings_products.csv").read()
    clients_csv = open_url("https://data.zuihe.com/dbd/core/state_08/clients.csv").read()
    savings_accounts_csv = open_url("https://data.zuihe.com/dbd/core/state_08/savings_accounts.csv").read()
    savings_account_transactions_csv = open_url("https://data.zuihe.com/dbd/core/state_08/savings_account_transactions.csv").read()
    gl_accounts_csv = open_url("https://data.zuihe.com/dbd/core/state_08/gl_accounts.csv").read()
    journal_entries_csv = open_url("https://data.zuihe.com/dbd/core/state_08/journal_entries.csv").read()
    charges_csv = open_url("https://data.zuihe.com/dbd/core/state_08/charges.csv").read()
    clearing_records_csv = open_url("https://data.zuihe.com/dbd/core/state_08/clearing_records.csv").read()
    import sqlite3, pandas as pd
    from io import StringIO
    conn = sqlite3.connect(':memory:')
    pd.read_csv(StringIO(savings_account_transactions_csv)).to_sql('savings_account_transactions', conn, index=False, if_exists='replace')
    result = pd.read_sql_query("""
        SELECT SUBSTR(transaction_date,1,7) AS month,
               SUM(CASE WHEN transaction_type='DEPOSIT' THEN amount ELSE 0 END) AS deposit_total,
               SUM(CASE WHEN transaction_type='WITHDRAWAL' THEN amount ELSE 0 END) AS withdrawal_total,
               SUM(CASE WHEN transaction_type='DEPOSIT' THEN amount ELSE 0 END) -
               SUM(CASE WHEN transaction_type='WITHDRAWAL' THEN amount ELSE 0 END) AS net_inflow
        FROM savings_account_transactions
        WHERE transaction_type IN ('DEPOSIT','WITHDRAWAL')
        GROUP BY month ORDER BY month
    """, conn)
    print(result.to_string(index=False))
    conn.close()