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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 blank_account(cls, db, addr, initial_nonce=0):
 """creates a blank account. :param db: :param addr: :param initial_nonce: :return: """

        db.put(BLANK_HASH, b"")
        o = cls(initial_nonce, 0, trie.BLANK_ROOT, BLANK_HASH, db, addr)
        o.existent_at_start = False
        return o