'List all snapshots.
:keyword location: Location used to filter
:type location: :class:`NodeLocation` or ``None``
:rtype: ``list`` of :class:`VolumeSnapshot`'

def ex_list_snapshots(self, location=None):

    action = self._get_project_action('volume/snapshot')
    params = {}
    if location:
        params['region'] = location.id
    response = self.connection.request(action, params=params)
    return self._to_snapshots(response.object)
