diff --git a/python/src/deltachat/__init__.py b/python/src/deltachat/__init__.py
index 83652d344..e5612b827 100644
--- a/python/src/deltachat/__init__.py
+++ b/python/src/deltachat/__init__.py
@@ -45,7 +45,7 @@ def py_dc_callback(ctx, evt, data1, data2):
         ret = callback(ctx, evt_name, data1, data2)
         if ret is None:
             ret = 0
-        assert isinstance(ret, int), repr(res)
+        assert isinstance(ret, int), repr(ret)
         if event_sig_types & 4:
             return ffi.cast('uintptr_t', ret)
         elif event_sig_types & 8:
diff --git a/python/tests/test_lowlevel.py b/python/tests/test_lowlevel.py
index 484a61795..dee19928e 100644
--- a/python/tests/test_lowlevel.py
+++ b/python/tests/test_lowlevel.py
@@ -2,7 +2,6 @@ from __future__ import print_function
 import pytest
 from deltachat import capi, Account, const, set_context_callback
 from deltachat.capi import ffi
-from deltachat.cutil import as_dc_charpointer
 from deltachat.account import EventLogger
 
 
@@ -10,6 +9,7 @@ def test_empty_context():
     ctx = capi.lib.dc_context_new(capi.ffi.NULL, capi.ffi.NULL, capi.ffi.NULL)
     capi.lib.dc_close(ctx)
 
+
 def test_dc_close_events():
     ctx = capi.lib.dc_context_new(capi.lib.py_dc_callback, ffi.NULL, ffi.NULL)
     evlog = EventLogger(ctx)