new_contents: class Solution(object):
      def canCompleteCircuit(self, gas, cost):
          """
          :type gas: List[int]
          :type cost: List[int]
          :rtype: int
          """
          tot, sum, start = 0, 0, 0
          for i in range(len(gas)):
              tot += gas[i] - cost[i]
              sum += gas[i] - cost[i]
              if sum < 0:
                  sum = 0
                  start = i + 1
          if tot < 0: return -1
          return start
  
subject: Create GasStation_001.py