import pandas as pd

orders = pd.DataFrame(
    {
        "order_id": [1001, 1002, 1003, 1004],
        "customer_id": ["C001", "C002", "C001", "C004"],
        "total_usd": [125.0, 240.0, 90.0, 410.0],
    }
)

customers = pd.DataFrame(
    {
        "customer_id": ["C001", "C002", "C003"],
        "segment": ["SMB", "Enterprise", "SMB"],
        "region": ["EMEA", "APAC", "AMER"],
    }
)