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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 _fsck(self, dry_run):
 """ Run a consistency check on this VersionStore library. """

        # Cleanup Orphaned Chunks
        self._cleanup_orphaned_chunks(dry_run)
        # Cleanup unreachable SHAs (forward pointers)
        self._cleanup_unreachable_shas(dry_run)
        # Cleanup Orphaned Snapshots
        self._cleanup_orphaned_versions(dry_run)