[Python] python Crypto Ed25519ph same processing(?) different signatures

in python i do (shorthand, code below, output below):

digest = SHA512.new(message)
signer = eddsa.new(privatekey, "rfc8032")
siganture = signer.sign(digest)


this gives the correct signature (see: Ed25519ph, TEST abc, https://datatracker.ietf.org/doc/html/rfc8032)

but when i print the intermediate hashed message (digest.hexdigest()) and use this as input for the signer i get a different signature???

signer = eddsa.new(privatekey, "rfc8032")
siganture = signer.sign(message_hashed)


then the signature is same as; Ed25519, TEST SHA(abc), https://datatracker.ietf.org/doc/html/rfc8032

the reason i am trying to get my head around this is because i cannot get the first (Ed25519ph, TEST abc) to work in arduino (also gives the second signature)

output:

python sign_problem.py

Ed25519ph: TEST abc
('Message (hex):', '616263')
('Caculated hash (hex):', 'ddaf35a193617abacc417349ae20413112e6fa4e89a97ea20a9eeee64b55d39a2192992a274fc1a836ba3c23a3feebbd454d4423643ce80e2a9ac94fa54ca49f')
('Caculated signature (hex):', '98A70222F0B8121AA9D30F813D683F809E462B469C7FF87639499BB94E6DAE4131F85042463C2A355A2003D062ADF5AAA10B8C61E636062AAAD11C2A26083406')

Ed25519ph: TEST abc: staring with hashed message
('Hashed message (hex):', 'DDAF35A193617ABACC417349AE20413112E6FA4E89A97EA20A9EEEE64B55D39A2192992A274FC1A836BA3C23A3FEEBBD454D4423643CE80E2A9AC94FA54CA49F')
('Caculated signature (hex):', 'DC2A4459E7369633A52B1BF277839A00201009A3EFBF3ECB69BEA2186C26B58909351FC9AC90B3ECFDFBC7C66431E0303DCA179C138AC17AD9BEF1177331A704')


code:

from Crypto.PublicKey import ECC
from Crypto.Signature import eddsa
from Crypto.Hash import SHA512

import hexdump

privatekey = eddsa.import_private_key(b'\x83\x3F\xE6\x24\x09\x23\x7B\x9D\x62\xEC\x77\x58\x75\x20\x91\x1E\x9A\x75\x9C\xEC\x1D\x19\x75\x5B\x7D\xA9\x01\xB9\x6D\xCA\x3D\x42')

print("")
print("Ed25519ph: TEST abc")

message = b'\x61\x62\x63'
print("Message (hex):",hexdump.dump(message, sep=""))

digest = SHA512.new(message)
print("Caculated hash (hex):", digest.hexdigest())
signer_1 = eddsa.new(privatekey, "rfc8032")
calculated_signature_1 = signer_1.sign(digest)
print("Caculated signature (hex):",hexdump.dump(calculated_signature_1, sep=""))

print("")
print("Ed25519ph: TEST abc: staring with hashed message")

message_hashed = b'\xDD\xAF\x35\xA1\x93\x61\x7A\xBA\xCC\x41\x73\x49\xAE\x20\x41\x31\x12\xE6\xFA\x4E\x89\xA9\x7E\xA2\x0A\x9E\xEE\xE6\x4B\x55\xD3\x9A\x21\x92\x99\x2A\x27\x4F\xC1\xA8\x36\xBA\x3C\x23\xA3\xFE\xEB\xBD\x45\x4D\x44\x23\x64\x3C\xE8\x0E\x2A\x9A\xC9\x4F\xA5\x4C\xA4\x9F'
print("Hashed message (hex):", hexdump.dump(message_hashed, sep=""))

signer_2 = eddsa.new(privatekey, "rfc8032")
calculated_signature_2 = signer_2.sign(message_hashed)
print("Caculated signature (hex):",hexdump.dump(calculated_signature_2, sep=""))



excerpt from https://datatracker.ietf.org/doc/html/rfc8032

-----TEST SHA(abc)

ALGORITHM:
Ed25519

SECRET KEY:
833fe62409237b9d62ec77587520911e
9a759cec1d19755b7da901b96dca3d42

PUBLIC KEY:
ec172b93ad5e563bf4932c70e1245034
c35467ef2efd4d64ebf819683467e2bf

MESSAGE (length 64 bytes):
ddaf35a193617abacc417349ae204131
12e6fa4e89a97ea20a9eeee64b55d39a
2192992a274fc1a836ba3c23a3feebbd
454d4423643ce80e2a9ac94fa54ca49f

SIGNATURE:
dc2a4459e7369633a52b1bf277839a00
201009a3efbf3ecb69bea2186c26b589
09351fc9ac90b3ecfdfbc7c66431e030
3dca179c138ac17ad9bef1177331a704
-----



and

-----TEST abc

ALGORITHM:
Ed25519ph

SECRET KEY:
833fe62409237b9d62ec77587520911e
9a759cec1d19755b7da901b96dca3d42

PUBLIC KEY:
ec172b93ad5e563bf4932c70e1245034
c35467ef2efd4d64ebf819683467e2bf

MESSAGE (length 3 bytes):
616263

SIGNATURE:
98a70222f0b8121aa9d30f813d683f80
9e462b469c7ff87639499bb94e6dae41
31f85042463c2a355a2003d062adf5aa
a10b8c61e636062aaad11c2a26083406
-----

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