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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 CheckHashes(self, hashes):
 """Check hashes against the filestore. Blobs use the hash in the schema: aff4:/files/hash/generic/sha256/[sha256hash] Args: hashes: A list of Hash objects to check. Yields: Tuples of (RDFURN, hash object) that exist in the store. """

    hash_map = {}
    for hsh in hashes:
      if hsh.HasField("sha256"):
        # The canonical name of the file is where we store the file hash.
        hash_map[aff4.ROOT_URN.Add("files/hash/generic/sha256").Add(
            str(hsh.sha256))] = hsh

    for metadata in aff4.FACTORY.Stat(list(hash_map)):
      yield metadata["urn"], hash_map[metadata["urn"]]