diff --git a/cashu/nostr/client/client.py b/cashu/nostr/client/client.py
index 3cb77662..3af7303b 100644
--- a/cashu/nostr/client/client.py
+++ b/cashu/nostr/client/client.py
@@ -45,9 +45,9 @@ def __init__(self, private_key: str = "", relays: List[str] = [], connect=True):
     def connect(self):
         for relay in self.relays:
             self.relay_manager.add_relay(relay)
-        self.relay_manager.open_connections({
-            "cert_reqs": ssl.CERT_NONE
-        })  # NOTE: This disables ssl certificate verification
+        self.relay_manager.open_connections(
+            {"cert_reqs": ssl.CERT_NONE}
+        )  # NOTE: This disables ssl certificate verification
 
     def close(self):
         self.relay_manager.close_connections()
@@ -105,13 +105,15 @@ def dm(self, message: str, to_pubkey: PublicKey):
         self.relay_manager.publish_event(dm)
 
     def get_dm(self, sender_publickey: PublicKey, callback_func=None, filter_kwargs={}):
-        filters = Filters([
-            Filter(
-                kinds=[EventKind.ENCRYPTED_DIRECT_MESSAGE],
-                pubkey_refs=[sender_publickey.hex()],
-                **filter_kwargs,
-            )
-        ])
+        filters = Filters(
+            [
+                Filter(
+                    kinds=[EventKind.ENCRYPTED_DIRECT_MESSAGE],
+                    pubkey_refs=[sender_publickey.hex()],
+                    **filter_kwargs,
+                )
+            ]
+        )
         subscription_id = os.urandom(4).hex()
         self.relay_manager.add_subscription(subscription_id, filters)
 
diff --git a/cashu/nostr/event.py b/cashu/nostr/event.py
index 6271e7ef..0ee7ad0b 100644
--- a/cashu/nostr/event.py
+++ b/cashu/nostr/event.py
@@ -77,18 +77,20 @@ def verify(self) -> bool:
         )
 
     def to_message(self) -> str:
-        return json.dumps([
-            ClientMessageType.EVENT,
-            {
-                "id": self.id,
-                "pubkey": self.public_key,
-                "created_at": self.created_at,
-                "kind": self.kind,
-                "tags": self.tags,
-                "content": self.content,
-                "sig": self.signature,
-            },
-        ])
+        return json.dumps(
+            [
+                ClientMessageType.EVENT,
+                {
+                    "id": self.id,
+                    "pubkey": self.public_key,
+                    "created_at": self.created_at,
+                    "kind": self.kind,
+                    "tags": self.tags,
+                    "content": self.content,
+                    "sig": self.signature,
+                },
+            ]
+        )
 
 
 @dataclass