comefrom: <doocs>1456.Maximum Number of Vowels in a Substring of Given Length_1.py
code: def maxVowels( s: str, k: int) -> int:
      vowels = set('aeiou')
      t = sum(c in vowels for c in s[:k])
      ans = t
      for i in range(k, len(s)):
          t += s[i] in vowels
          t -= s[i - k] in vowels
          ans = max(ans, t)
      return ans
masked: def sample_funcname ( var_0 : str , var_2 : int ) -> int :
      var_6 = set ( 'aeiou' )
      var_9 = sum ( var_8 in var_6 for var_8 in var_0 [ : var_2 ] )
      var_10 = var_9
      for var_13 in range ( var_2 , len ( var_0 ) ) :
          var_9 += var_0 [ var_13 ] in var_6
          var_9 -= var_0 [ var_13 - var_2 ] in var_6
          var_10 = max ( var_10 , var_9 )
      return var_10
  