docs: def filter(self, func):
          """
          :param func:
          :type func: (K, T) -> bool
          :rtype: TList[T]
  
          Usage:
  
              >>> TDict(k1=1, k2=2, k3=3).filter(lambda k, v: v < 2)
              [1]
          """
          return TList([v for k, v in self.items() if func(k, v)])