Final answer:
A Software Engineer is responsible for creating computer code for new and existing systems software. They contribute significantly to the quaternary sector of the economy and generally focus on professional tasks that utilize their specialized skills.
Step-by-step explanation:
The professional who creates the computer code for developing new systems software or maintaining existing systems software is a Software Engineer. Software engineers design, develop, and test software, ensuring that we have functional systems for a variety of purposes, from running our computers to operating cars and much more. They work for companies such as Microsoft, Apple, and Hewlett Packard and play a vital role in the quaternary sector of the economy, which involves intellectual activities associated with technological and knowledge-based services.
While a computer systems engineer could technically paint their own house, it is usually more efficient for them to hire a painter. This is because the engineer's time is better spent on professional activities that make better use of their specialized skills and may provide a higher financial return than what they would save by painting the house themselves.