update requests_oauthlib

lib/requests_oauthlib/compliance_fixes/mailchimp.py

@@ -1,21 +1,19 @@
 import json
 
-from oauthlib.common import to_unicode
-
 
 def mailchimp_compliance_fix(session):
     def _null_scope(r):
         token = json.loads(r.text)
         if "scope" in token and token["scope"] is None:
             token.pop("scope")
-        r._content = to_unicode(json.dumps(token)).encode("utf-8")
+        r._content = json.dumps(token).encode()
         return r
 
     def _non_zero_expiration(r):
         token = json.loads(r.text)
         if "expires_in" in token and token["expires_in"] == 0:
             token["expires_in"] = 3600
-        r._content = to_unicode(json.dumps(token)).encode("utf-8")
+        r._content = json.dumps(token).encode()
         return r
 
     session.register_compliance_hook("access_token_response", _null_scope)