what format is public key?

[cloudkeychain]

What format is the public key in the sample input file?

[pikachunakapika]

Format is hex(x)[2:].zfill(64)+hex(y)[2:].zfill(64):

aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff

Where

X = aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
Y = ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff

No leading 03 or 04 from bitcoin encoded format.
Make sure you leftpad X, Y with zeros to fill 64 characters