diff --git a/environment.yml b/environment.yml
index 82aff0aa..1e210615 100644
--- a/environment.yml
+++ b/environment.yml
@@ -14,7 +14,7 @@ dependencies:
   - matplotlib
   # testing and developing
   - pdbpp
-  - country_converter >= 0.7.7
+  - country_converter >= 0.8.0
   - pytest >= 5.4.3
   - isort >= 5.6.0
   - pytest-black
diff --git a/pymrio/core/mriosystem.py b/pymrio/core/mriosystem.py
index 37900c32..10f0952a 100644
--- a/pymrio/core/mriosystem.py
+++ b/pymrio/core/mriosystem.py
@@ -2439,14 +2439,10 @@ def aggregate(
                     extension.__dict__[ik_name].columns = mi_reg_sec
                     extension.__dict__[ik_name].index = mi_reg_sec
                     st_redo_unit = True
-                elif (
-                    ik_df.index.names
-                    == [
-                        "region",
-                        "sector",
-                    ]
-                    and ik_df.columns.names == ["region", "category"]
-                ):
+                elif ik_df.index.names == [
+                    "region",
+                    "sector",
+                ] and ik_df.columns.names == ["region", "category"]:
 
                     # Full disaggregated finald demand satellite account.
                     # Thats not implemented yet - but aggregation is in place
diff --git a/tests/test_core.py b/tests/test_core.py
index 0a1626d1..08e7da83 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -343,8 +343,6 @@ def test_characterize_extension(fix_testmrio):
         check_names=False,
     )
 
-    return locals()
-
 
 def test_reset_to_flows(fix_testmrio):
     tt = fix_testmrio.testmrio