'Retrieve a list of available snapshots (a.k.a. shadow copies) for *path*.
Note that snapshot features are only supported on Windows Vista Business, Enterprise and Ultimate, and on all Windows 7 editions.
:param string/unicode service_name: the name of the shared folder for the *path*
:param string/unicode path: path relative to the *service_name* where we are interested in the list of available snapshots
:return: A *twisted.internet.defer.Deferred* instance. The callback function will be called with a list of python *datetime.DateTime*
instances in GMT/UTC time zone'

def listSnapshots(self, service_name, path, timeout=30):

    if (not self.instance):
        raise NotConnectedError('Not    connected    to    server')
    d = defer.Deferred()
    self.instance._listSnapshots(service_name, path, d.callback, d.errback, timeout=timeout)
    return d
