diff --git a/src/aleph/sdk/chains/cosmos.py b/src/aleph/sdk/chains/cosmos.py
index 465028e1..53b32d04 100644
--- a/src/aleph/sdk/chains/cosmos.py
+++ b/src/aleph/sdk/chains/cosmos.py
@@ -4,12 +4,12 @@
 from typing import Union
 
 import ecdsa
-from ecdsa.keys import BadSignatureError as ECDSABadSignatureError
 from cosmospy._wallet import privkey_to_address, privkey_to_pubkey
+from ecdsa.keys import BadSignatureError as ECDSABadSignatureError
 from ecies import encrypt
 
-from .common import BaseAccount, get_fallback_private_key, get_verification_buffer
 from ..exceptions import BadSignatureError
+from .common import BaseAccount, get_fallback_private_key, get_verification_buffer
 
 DEFAULT_HRP = "cosmos"
 
diff --git a/tests/unit/test_chain_cosmos.py b/tests/unit/test_chain_cosmos.py
index 3751ee9a..30301aa3 100644
--- a/tests/unit/test_chain_cosmos.py
+++ b/tests/unit/test_chain_cosmos.py
@@ -96,6 +96,4 @@ async def test_verify_signature_with_forged_signature(cosmos_account):
 
     forged_signature = base64.b64encode(bytes(64)).decode("utf-8")
     with pytest.raises(BadSignatureError):
-        verify_signature(
-            forged_signature, public_key, get_verification_string(message)
-        )
+        verify_signature(forged_signature, public_key, get_verification_string(message))