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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(hash_ids):
 """Checks if files with given hashes are present in the file store. Args: hash_ids: A list of SHA256HashID objects. Returns: A dict where SHA256HashID objects are keys. Corresponding values may be False (if hash id is not present) or True if it is not present. """

  return {
      k: bool(v)
      for k, v in data_store.REL_DB.ReadHashBlobReferences(hash_ids).items()
  }