text: class Solution(object):
      def removeDuplicates(self, nums):
          """
          :type nums: List[int]
          :rtype: int
          """
          n=len(nums)
          if n==0:
              return 0
          if n==1:
              return 1
          i=1
          while i<len(nums):
              if nums[i]==nums[i-1]:
                  nums.pop(i)
              else:
                  i+=1
          return len(nums)