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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):
 """ Deletes the current instance. This assumes that we know what we're doing, and have a primary key in our data already. If this is a new instance, then we'll let the user know with an Exception """

        if self._new:
            raise Exception("This is a new object, %s not in data, \
indicating this entry isn't stored." % self.primaryKey)

        r.table(self.table).get(self._data[self.primaryKey]) \
            .delete(durability=self.durability).run(self._conn)
        return True