diff --git a/blockchain_integration/pi_network/config/environment_variables.py b/blockchain_integration/pi_network/config/environment_variables.py
index 4514cec3b..1f53e2911 100644
--- a/blockchain_integration/pi_network/config/environment_variables.py
+++ b/blockchain_integration/pi_network/config/environment_variables.py
@@ -1,15 +1,17 @@
-import os
 import json
+import os
+
 from cryptography.fernet import Fernet
 
+
 class EnvironmentVariables:
     def __init__(self):
-        self.env_file = os.path.join(os.path.dirname(__file__), 'env.json')
+        self.env_file = os.path.join(os.path.dirname(__file__), "env.json")
         self.env_data = self.load_env_data()
 
     def load_env_data(self):
         if os.path.exists(self.env_file):
-            with open(self.env_file, 'r') as f:
+            with open(self.env_file, "r") as f:
                 env_data = json.load(f)
                 return env_data
         else:
@@ -18,32 +20,36 @@ def load_env_data(self):
     def get_variable(self, key: str):
         if key in self.env_data:
             encrypted_value = self.env_data[key]
-            fernet = Fernet(os.environ['FERNET_KEY'])
+            fernet = Fernet(os.environ["FERNET_KEY"])
             decrypted_value = fernet.decrypt(encrypted_value.encode()).decode()
             return decrypted_value
         else:
             return None
 
     def set_variable(self, key: str, value: str):
-        fernet = Fernet(os.environ['FERNET_KEY'])
+        fernet = Fernet(os.environ["FERNET_KEY"])
         encrypted_value = fernet.encrypt(value.encode()).decode()
         self.env_data[key] = encrypted_value
-        with open(self.env_file, 'w') as f:
+        with open(self.env_file, "w") as f:
             json.dump(self.env_data, f)
 
     def delete_variable(self, key: str):
         if key in self.env_data:
             del self.env_data[key]
-            with open(self.env_file, 'w') as f:
+            with open(self.env_file, "w") as f:
                 json.dump(self.env_data, f)
 
+
 env_vars = EnvironmentVariables()
 
+
 def get_env_var(key: str):
     return env_vars.get_variable(key)
 
+
 def set_env_var(key: str, value: str):
     env_vars.set_variable(key, value)
 
+
 def delete_env_var(key: str):
     env_vars.delete_variable(key)