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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 index_one(self, instance, force=False):
 """ Indexes exactly one object of the Ambry system. Args: instance (any):
 instance to index. force (boolean):
 if True replace document in the index. Returns: boolean: True if document added to index, False if document already exists in the index. """

        if not self.is_indexed(instance) and not force:
            doc = self._as_document(instance)
            self._index_document(doc, force=force)
            logger.debug('{} indexed as\n {}'.format(instance.__class__, pformat(doc)))
            return True

        logger.debug('{} already indexed.'.format(instance.__class__))
        return False