For testing purpose you can replace the challenge line in the python script with this:
challenge = Public_key(g, Point( sex, 0x2f01e5e15cca351daff3843fb70f3c2f0a1bdd05e5af888a67784ef3e10a2a01L, 0x5c4da8a741539949293d082a132d13b4c2e213d6ba5b7617b5da2cb76cbde904L))
In this case
k=8Your script must to be fixed.
The K value for the test pubkey : 042f01e5e15cca351daff3843fb70f3c2f0a1bdd05e5af888a67784ef3e10a2a015c4da8a741539
949293d082a132d13b4c2e213d6ba5b7617b5da2cb76cbde904
is correctly 8, but your script validated 0xfffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd036413a like a correct value, and not the 8
FaSan