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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 _query_string_params(flask_request):
 """ Constructs an APIGW equivalent query string dictionary Parameters flask_request request Request from Flask Returns dict (str: str) ------- Empty dict if no query params where in the request otherwise returns a dictionary of key to value """

        query_string_dict = {}

        # Flask returns an ImmutableMultiDict so convert to a dictionary that becomes
        # a dict(str: list) then iterate over
        for query_string_key, query_string_list in flask_request.args.lists():
            query_string_value_length = len(query_string_list)

            # if the list is empty, default to empty string
            if not query_string_value_length:
                query_string_dict[query_string_key] = ""
            else:
                # APIGW doesn't handle duplicate query string keys, picking the last one in the list
                query_string_dict[query_string_key] = query_string_list[-1]

        return query_string_dict