def disconnect(self):
        for connection in self.hosts.itervalues():
            connection.disconnect()
Validate that the cache_path field is provided if required.
dataset/ETHPy150Open disqus/nydus/nydus/db/base.py/BaseCluster.disconnect--crossover with--dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/admin/forms.py/GeneralSettingsForm.clean_cache_path