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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 __get_method_abbrev(self):
 """Abbreviated form of clustering method parameter. Used to guess output filenames for MOTHUR. """

        abbrevs = {
            'furthest': 'fn',
            'nearest': 'nn',
            'average': 'an',
        }
        if self.Parameters['method'].isOn():
            method = self.Parameters['method'].Value
        else:
            method = self.Parameters['method'].Default
        return abbrevs[method]