Function will return maximum sum of sub array of an array

maxSumOfSubarray.py

def maxSubArray(A):
        maxSumSoFar = 0 
        currentMaxSum = 0
        for i in range(0, len(A)) :
            currentMaxSum += A[i]
            if currentMaxSum < 0 :
                currentMaxSum = 0
            if maxSumSoFar < currentMaxSum :
                maxSumSoFar = currentMaxSum
        if maxSumSoFar == 0 and max(A) >= 0 :
            return 0
        elif maxSumSoFar == 0 and max(A) < 0 :
            return max(A)
        else :
            return maxSumSoFar
# For [−2,1,−3,4,−1,2,1,−5,4] value of A it will return -6
# For [-500] it will return -500