500. 键盘行

from typing import List

class Solution:
   @staticmethod
   def is_inside(word: str, line: str) -> bool:
       return len(set(word).difference(set(line))) == 0

   def is_inside_one_line(self, word: str) -> bool:
       return self.is_inside(word.lower(), 'qwertyuiop') \
              or self.is_inside(word.lower(), 'asdfghjkl') \
              or self.is_inside(word.lower(), 'zxcvbnm')

   def findWords(self, words: List[str]) -> List[str]:
       return list(filter(self.is_inside_one_line, words))