leetcode Search in Rotated Sorted Array python

#Suppose a sorted array is rotated at some pivot unknown to you beforehand.

#(i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2).

#You are given a target value to search. If found in the array return its index, otherwise return -1.

#You may assume no duplicate exists in the array.

class Solution(object):
    def search(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: int
        """
        left=0
        right=len(nums)-1
        while left <= right:
            mid = (left+right)/2
            if target == nums[mid]:
                return mid
            if nums[mid] >= nums[left]:
                if target < nums[mid] and target >= nums[left]:
                    right=mid-1
                else:
                    left=mid+1
            elif nums[mid] < nums[right]:
                if target > nums[mid] and target <= nums[right]:
                    left=mid+1
                else:
                    right=mid-1
        return -1