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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 _r1r2_standard(self, word, vowels):
 """ Return the standard interpretations of the string regions R1 and R2. R1 is the region after the first non-vowel following a vowel, or is the null region at the end of the word if there is no such non-vowel. R2 is the region after the first non-vowel following a vowel in R1, or is the null region at the end of the word if there is no such non-vowel. :param word: The word whose regions R1 and R2 are determined. :type word: str or unicode :param vowels: The vowels of the respective language that are used to determine the regions R1 and R2. :type vowels: unicode :return: (r1,r2), the regions R1 and R2 for the respective word. :rtype: tuple :note: This helper method is invoked by the respective stem method of the subclasses DutchStemmer, FinnishStemmer, FrenchStemmer, GermanStemmer, ItalianStemmer, PortugueseStemmer, RomanianStemmer, and SpanishStemmer. It is not to be invoked directly! :note: A detailed description of how to define R1 and R2 can be found at http://snowball.tartarus.org/texts/r1r2.html """

        r1 = ""
        r2 = ""
        for i in range(1, len(word)):
            if word[i] not in vowels and word[i-1] in vowels:
                r1 = word[i+1:]
                break

        for i in range(1, len(r1)):
            if r1[i] not in vowels and r1[i-1] in vowels:
                r2 = r1[i+1:]
                break

        return (r1, r2)