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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def known(self, words):
 """ The subset of `words` that appear in the dictionary of words Args: words (list):
 List of words to determine which are in the \ corpus Returns: set: The set of those words from the input that are in the \ corpus """

        tmp = [w.lower() for w in words]
        return set(
            w
            for w in tmp
            if w in self._word_frequency.dictionary
            or not self._check_if_should_check(w)
        )