80 Remove Duplicates from Sorted Array II

def removeDuplicates(self,nums):
        if len(nums) == 0:
            return 0
        length,index = 1,1
        while index < len(nums):
            counter = 1
            if nums[index] == nums[index-1]:
                length += 1
                while index < len(nums) and nums[index] == nums[index-1]:
                    counter += 1
                    if counter > 2:
                        nums[index:index+1] = [] #remove duplicated element that are more than two
                    else:
                        index += 1
            else:
                length += 1
                index += 1