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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 delete_suffixes(self, word):
 """ Delete some very common suffixes. """

        length = len(word)
        suffixes = ['al', 'ance', 'ence', 'er', 'ic', 'able', 'ible',
                    'ant', 'ement', 'ment', 'ent', 'ism', 'ate',
                    'iti', 'ous', 'ive', 'ize']

        for suffix in suffixes:
            if word.endswith(suffix) and self.r2 <= (length - len(suffix)):
                word = word[:-len(suffix)]
                return word

        if word.endswith('ion') and self.r2 <= (length - 3):
            if word[length - 4] in 'st':
                word = word[:-3]

        return word