python3: encoding variations in auth_fc testing

tests/auth_fc/test_auth_fc.py

@@ -28,6 +28,7 @@ import requests
 
 from django.core.urlresolvers import reverse
 from django.contrib.auth import get_user_model
+from django.utils.encoding import force_text
 from django.utils.six.moves.urllib import parse as urlparse
 from django.utils.timezone import now
 
@@ -56,7 +57,8 @@ def get_links_from_mail(mail):
 
 def hmac_jwt(payload, key):
     header = {'alg': 'HS256'}
-    k = jwk.JWK(kty='oct', k=base64.b64encode(key.encode('utf-8')))
+    k = jwk.JWK(
+            kty='oct', k=force_text(base64.b64encode(key.encode('utf-8'))))
     t = jwt.JWT(header=header, claims=payload)
     t.make_signed_token(k)
     return t.serialize()