In linear time, find the maximum sum of all possible contiguous subarrays

[DPaul]

I ran several tests with both proposed codes, up to len(arr) = 100,
and I get the same results.
So for what it's worth:

maxArr = [max(arr)]
for number in range(len(arr)):
    for grouping in range(2,len(arr)-number+1):
        maxArr.append(sum(arr[number:(number+grouping)]))
print(max(maxArr))    

Paul