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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 inverse_removing(self, words_to_remove):
 """Returns a string after removing the appropriate words. If self.bow is false, replaces word with UNKWORDZ instead of removing it. Args: words_to_remove: list of ids (ints) to remove Returns: original raw string with appropriate words removed. """

        mask = np.ones(self.as_np.shape[0], dtype='bool')
        mask[self.__get_idxs(words_to_remove)] = False
        if not self.bow:
            return ''.join([self.as_list[i] if mask[i]
                            else 'UNKWORDZ' for i in range(mask.shape[0])])
        return ''.join([self.as_list[v] for v in mask.nonzero()[0]])