Leetcode: Search Insert Position @Python

class Solution:
    # @param A, a list of integers
    # @param target, an integer to be inserted
    # @return integer
    def searchInsert(self, A, target):
        left=0
        right=len(A)-1
        while left<=right:
            middle=int((left+right)/2)
            if target<A[middle]:
                right=middle-1
            elif target==A[middle]:
                return middle
            else:
                left=middle+1                
        return middle if target<A[middle] else middle+1