您如何使用 AI 编写数据迁移和格式转换脚本？

import csv

# Source CSV: id,email,signup_date  (signup_date may be blank)
# Target table: users(id INT, email TEXT NOT NULL, signup_date DATE NULL)
def csv_to_sql(path: str) -> list[str]:
    statements = []
    with open(path, newline="", encoding="utf-8") as f:
        for row in csv.DictReader(f):
            email = row["email"].strip()
            if not email:                      # validate: skip invalid rows, don't insert garbage
                continue
            date = row["signup_date"].strip() or None
            email_sql = email.replace("'", "''")   # escape quotes to avoid broken SQL / injection
            date_sql = f"'{date}'" if date else "NULL"
            # ON CONFLICT makes it idempotent: re-running won't create duplicates
            statements.append(
                f"INSERT INTO users (id, email, signup_date) "
                f"VALUES ({int(row['id'])}, '{email_sql}', {date_sql}) "
                f"ON CONFLICT (id) DO NOTHING;"
            )
    return statements