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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 ed25519_private_key_from_string(string):
 """Create an ed25519 private key from ``string``, which is a seed. Args: string (str):
 the string to use as a seed. Returns: Ed25519PrivateKey: the private key """

    try:
        return Ed25519PrivateKey.from_private_bytes(
            base64.b64decode(string)
        )
    except (UnsupportedAlgorithm, Base64Error) as exc:
        raise ScriptWorkerEd25519Error("Can't create Ed25519PrivateKey: {}!".format(str(exc)))