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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 get_signed_raw_revocation_document(identity: Identity, salt: str, password: str) -> str: """ Generate account revocation document for given identity :param identity: Self Certification of the identity :param salt: Salt :param password: Password :rtype: str """

    revocation = Revocation(PROTOCOL_VERSION, identity.currency, identity, "")

    key = SigningKey.from_credentials(salt, password)
    revocation.sign([key])
    return revocation.signed_raw()