pub fn generate_empty_sector_update_proof<Tree: 'static + MerkleTreeTrait<Hasher = TreeRHasher>>(
porep_config: PoRepConfig,
comm_r_old: Commitment,
comm_r_new: Commitment,
comm_d_new: Commitment,
sector_key_path: &Path,
sector_key_cache_path: &Path,
replica_path: &Path,
replica_cache_path: &Path
) -> Result<EmptySectorUpdateProof>