What are the headquarters that have both a company in the banking and 'oil and gas' industries?
SELECT headquarters FROM company WHERE main_industry  =  'Banking' INTERSECT SELECT headquarters FROM company WHERE main_industry  =  'Oil and gas'
SELECT headquarters FROM company WHERE main_industry  =  'Banking' INTERSECT SELECT headquarters FROM company WHERE main_industry  =  'Oil and gas'
[{'Headquarters': 'China'}, {'Headquarters': 'UK'}, {'Headquarters': 'USA'}]