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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 CountClientPlatformReleasesByLabel(self, day_buckets):
 """Computes client-activity stats for OS-release strings in the DB."""

    return self._CountClientStatisticByLabel(
        day_buckets, lambda client_info: client_info.last_snapshot.Uname())