<|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 function that takes in two arrays of integers and returns the sum of the elements in both arrays.
array1 = [1, 2, 3] 
array2 = [4, 5, 6]<|im_end|>
<|im_start|>assistant
def sum_arrays(arr1, arr2):
    sums = []
    for i in range(len(arr1)):
        sums.append(arr1[i] + arr2[i])
    return sums<|im_end|>
