What are the shipping agent names?
SELECT shipping_agent_name FROM Ref_Shipping_Agents;
SELECT shipping_agent_name FROM Ref_Shipping_Agents;
[{'shipping_agent_name': 'UPS'}, {'shipping_agent_name': 'USPS'}, {'shipping_agent_name': 'Airline'}, {'shipping_agent_name': 'Fedex'}, {'shipping_agent_name': 'Ship'}]