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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 configure_encryptor(graph):
 """ Create a MultiTenantEncryptor from configured keys. """

    encryptor = graph.multi_tenant_key_registry.make_encryptor(graph)

    # register the encryptor will each encryptable type
    for encryptable in EncryptableMixin.__subclasses__():
        encryptable.register(encryptor)

    return encryptor