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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 __r1_hungarian(self, word, vowels, digraphs):
 """ Return the region R1 that is used by the Hungarian stemmer. If the word begins with a vowel, R1 is defined as the region after the first consonant or digraph (= two letters stand for one phoneme) in the word. If the word begins with a consonant, it is defined as the region after the first vowel in the word. If the word does not contain both a vowel and consonant, R1 is the null region at the end of the word. :param word: The Hungarian word whose region R1 is determined. :type word: str or unicode :param vowels: The Hungarian vowels that are used to determine the region R1. :type vowels: unicode :param digraphs: The digraphs that are used to determine the region R1. :type digraphs: tuple :return: the region R1 for the respective word. :rtype: unicode :note: This helper method is invoked by the stem method of the subclass HungarianStemmer. It is not to be invoked directly! """

        r1 = ""
        if word[0] in vowels:
            for digraph in digraphs:
                if digraph in word[1:]:
                    r1 = word[word.index(digraph[-1])+1:]
                    return r1

            for i in range(1, len(word)):
                if word[i] not in vowels:
                    r1 = word[i+1:]
                    break
        else:
            for i in range(1, len(word)):
                if word[i] in vowels:
                    r1 = word[i+1:]
                    break

        return r1