class Solution:
    def findRepeatedDnaSequences(self, s):
        """
        :type s: str
        :rtype: List[str]
        """
        if len(s) <= 10:
            return []
        out_lst = set()
        charDict = set()
        for i in range(9, len(s)):
            sub_str = s[i-9:i+1]
            len(sub_str)
            if sub_str in charDict:
                out_lst.add(sub_str)
            else:
                charDict.add(sub_str)
        return list(out_lst)