diff --git a/banking/transaction_processing.py b/banking/transaction_processing.py
index 21924650b..b383fe632 100644
--- a/banking/transaction_processing.py
+++ b/banking/transaction_processing.py
@@ -2,6 +2,7 @@
 
 import logging
 
+
 def deposit(account_id: int, amount: float) -> bool:
     """
     Deposit an amount into an account.
@@ -18,13 +19,14 @@ def deposit(account_id: int, amount: float) -> bool:
         account = get_account_by_id(account_id)
         if amount < 0:
             raise ValueError("Amount cannot be negative")
-        account['balance'] += amount
+        account["balance"] += amount
         save_account(account)
         return True
     except Exception as e:
         logging.error(f"Error depositing into account {account_id}: {e}")
         return False
 
+
 def withdraw(account_id: int, amount: float) -> bool:
     """
     Withdraw an amount from an account.
@@ -41,15 +43,16 @@ def withdraw(account_id: int, amount: float) -> bool:
         account = get_account_by_id(account_id)
         if amount < 0:
             raise ValueError("Amount cannot be negative")
-        if account['balance'] < amount:
+        if account["balance"] < amount:
             raise ValueError("Insufficient balance")
-        account['balance'] -= amount
+        account["balance"] -= amount
         save_account(account)
         return True
     except Exception as e:
         logging.error(f"Error withdrawing from account {account_id}: {e}")
         return False
 
+
 def transfer(from_account_id: int, to_account_id: int, amount: float) -> bool:
     """
     Transfer an amount between two accounts.
@@ -63,7 +66,9 @@ def transfer(from_account_id: int, to_account_id: int, amount: float) -> bool:
         bool: True if the transfer was successful, False otherwise.
     """
     try:
-        logging.info(f"Transferring {amount} from account {from_account_id} to account {to_account_id}")
+        logging.info(
+            f"Transferring {amount} from account {from_account_id} to account {to_account_id}"
+        )
         if not withdraw(from_account_id, amount):
             return False
         if not deposit(to_account_id, amount):