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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 find_suggestions(self, sentence):
 """ Search all possible suggestions. Suggestions returned always have at least one document matching. Arguments: sentence --- keywords (single strings) for which we want suggestions Return: An array of sets of keywords. Each set of keywords (-> one string) is a suggestion. """

        if not isinstance(sentence, str):
            sentence = str(sentence)

        keywords = sentence.split(" ")

        query_parser = self.search_param_list['strict'][0]['query_parser']

        base_search = u" ".join(keywords).strip()
        final_suggestions = []
        corrector = self.__searcher.corrector("content")
        label_corrector = self.__searcher.corrector("label")
        for (keyword_idx, keyword) in enumerate(keywords):
            if (len(keyword) <= MIN_KEYWORD_LEN):
                continue
            keyword_suggestions = label_corrector.suggest(
                keyword, limit=2
            )[:]
            keyword_suggestions += corrector.suggest(keyword, limit=5)[:]
            for keyword_suggestion in keyword_suggestions:
                new_suggestion = keywords[:]
                new_suggestion[keyword_idx] = keyword_suggestion
                new_suggestion = u" ".join(new_suggestion).strip()

                if new_suggestion == base_search:
                    continue

                # make sure it would return results
                query = query_parser.parse(new_suggestion)
                results = self.__searcher.search(query, limit=1)
                if len(results) <= 0:
                    continue
                final_suggestions.append(new_suggestion)
        final_suggestions.sort()
        return final_suggestions