Potential signature generator method for MemberSuite SOAP API

signature.py

from base64 import b64encode

from hashlib import sha1
import hmac


def hash_signature(url, association_id, secret_access_key, session_id=None):
    """
    Process from Membersuite Docs: http://bit.ly/2eSIDxz
    """

    data = "%s%s" % (url, association_id)
    if session_id:
        data = "%s%s" % (data, session_id)

    data_b = bytearray(data, 'utf-8')
    secret_b = bytearray(secret_access_key, 'utf-8')

    hashed = hmac.new(secret_b, data_b, sha1)
    return hashed.digest().encode("base64").rstrip('\n')
  
"""
  TESTS
"""
import unittest


class SignatureTest(unittest.TestCase):
    def test(self):

        secret = u'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=='
        url = u"http://membersuite.com/contracts/IConciergeAPIService/WhoAmI"
        association_id = u"00000000-0000-0000-0000-000000000000"
        session_id = u"11111111-1111-1111-1111-111111111111"
        self.assertEqual(
            hash_signature(url, association_id, secret, session_id),
            "2zsMYdHb/MJUeTjv5cQl5pBuIqU=")

if __name__ == '__main__':
    unittest.main()

Test from documentation, not currently passing. Why?

usage: python signature.py to test.