Import and export of goods; machinery and equipment leasing (excluding car rental). (Enterprises shall, in accordance with the law, choose to operate their own projects and carry out business activities; they shall carry out business activities in accordance with the approved contents after approval by the relevant departments in accordance with the law; they shall not engage in the business activities of the city's industrial policy prohibition and restriction projects.) , Technical services, technology promotion, technical advice; product design; sales of self-developed products, machinery and equipment, electronic products; import and export of goods; machinery and equipment leasing (excluding car rental). (Enterprises shall, in accordance with the law, choose to operate their own projects and carry out business activities; they shall go through the approved projects according to law and carry out business activities according to the approved contents after approval by the relevant departments;