pss signatures python

1>>> from Crypto.Signature import pss
2>>> from Crypto.Hash import SHA256
3>>> from Crypto.PublicKey import RSA
4>>> from Crypto import Random
5>>>
6>>> message = 'To be signed'
7>>> key = RSA.import_key(open('privkey.der').read())
8>>> h = SHA256.new(message)
9>>> signature = pss.new(key).sign(h)
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