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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 sorted(self, fsort):
        '''
        Allows to add one or more sort on specific fields. Each sort can be reversed as well. The sort is defined on a per field level, with special field name for _score to sort by score.
        '''
        if not self.params:
            self.params = dict()
        self.params['sort'] = fsort

        return self