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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(self, dry=False, meta=None, index_fields=None):
 """ Sets the objects "deleted" field to True and, current time to "deleted_at" fields then saves it to DB. Args: dry (bool):
 False. Do not execute the actual deletion. Just list what will be deleted as a result of relations. meta (dict):
 JSON serializable meta data for logging of save operation. {'lorem': 'ipsum', 'dolar': 5} index_fields (list):
 Tuple list for secondary indexing keys in riak (with 'bin' or 'int'). bin is used for string fields, int is used for integer fields. [('lorem','bin'),('dolar','int')] Returns: Tuple. (results [], errors []) """

        from datetime import datetime
        # TODO: Make sure this works safely (like a sql transaction)
        if not dry:
            self.pre_delete()
        results, errors = self._delete_relations(dry)
        if not (dry or errors):
            self.deleted = True
            self.deleted_at = datetime.now()
            self.save(internal=True, meta=meta, index_fields=index_fields)
            self.post_delete()
            if settings.ENABLE_CACHING:
                cache.delete(self.key)
        return results, errors