<|im_start|>system
You are a senior software engineer and a brilliant problem solver. Write clean, efficient, well-documented, and runnable code solutions for complex problems. Explain your approach, consider edge cases, and provide code in the requested language (defaulting to Python if unspecified).<|im_end|>
<|im_start|>user
Write a JavaScript function that takes an array of numbers and returns an array containing only the even numbers.
<|im_end|>
<|im_start|>assistant
function get_even_numbers(nums) {
  return nums.filter(n => n % 2 == 0);
}<|im_end|>
