Max Sum Subarray or Kadane's algorithm

This problem was asked by Amazon.

Given an array of numbers, find the maximum sum of any contiguous subarray of the array.

For example, given the array [34, -50, 42, 14, -5, 86], the maximum sum would be 137, since we would take elements 42, 14, -5, and 86.

Given the array [-5, -1, -8, -9], the maximum sum would be 0, since we would not take any elements.

Do this in O(N) time.

My Solution(Python):

def maxSumSubarray(A: list) -> int:
    max_so_far = 0
    max_ending_here = 0
    for a in A:
        max_ending_here = max_ending_here + a
        if max_ending_here < 0:
            max_ending_here = 0
        if max_ending_here > max_so_far:
            max_so_far = max_ending_here
        print('a=%i, meh=%i, msf=%s' %(a, max_ending_here, max_so_far))
    return max_so_far

A = [34, -50, 42, 14, -5, 86]
print(maxSumSubarray(A))
A = [-5, -1, -8, -9]
print(maxSumSubarray(A))
A = [34, -16]
print(maxSumSubarray(A))
A = [-16, 34]
print(maxSumSubarray(A))