คำอธิบายของประเภทของบริษัทที่สรุปสัญญาล่าสุดคืออะไร?ไม่จำเป็นต้องใช้ตารางทั้งหมด
What is the description of the type of the company who concluded its contracts most recently?It is not neccessary to use all the tables.
 skills_required_to_fix:  part_fault_id [ number]  skill_id [ number] 
SELECT T1.company_name FROM third_party_companies AS T1 JOIN maintenance_contracts AS T2 ON T1.company_id = T2.maintenance_contract_company_id JOIN Ref_Company_Types AS T3 ON T1.company_type_code = T3.company_type_code ORDER BY T2.contract_end_date DESC LIMIT 1