python 找数组中最大子序列和

def findMaxNum(arr):
sum = 0
max = arr[0]
for data in arr:
if(sum >= 0):
sum += data
else:
sum = data
if(sum > max):
max = sum
return max

if __name__ == '__main__':
a = [6,-2,5,-3,-5,1,-2]
max = findMaxNum(a)
print max