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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 assure_snapshot(fnc):
 """ Converts a snapshot ID passed as the snapshot to a CloudBlockStorageSnapshot object. """

    @wraps(fnc)
    def _wrapped(self, snapshot, *args, **kwargs):
        if not isinstance(snapshot, CloudBlockStorageSnapshot):
            # Must be the ID
            snapshot = self._snapshot_manager.get(snapshot)
        return fnc(self, snapshot, *args, **kwargs)
    return _wrapped