Make a file and authenticate if user exists

auth.py

@@ -1,5 +1,6 @@
 import json
 import getpass
+import os
 
 PATH = "./pwdb.json"
 
@@ -8,31 +9,41 @@ def get_credentials():
     password = getpass.getpass("Password: ")
     return username, password
 
-def read_pwdb():
-    with open(PATH, "rt") as f:
-        pwdb = json.load(f)
+def read_pwdb(username, password):
+    if os.path.exists(PATH):
+        pwdb={}
+        with open(PATH, "rt") as f:
+            pwdb = json.load(f)
+        authenticate(username, password, pwdb)    
+    else:
+        pwdb=add_user(username, password, pwdb={})
+        write_pwdb(pwdb)
+        print("First user added!")
     return pwdb
 
+
 def write_pwdb(pwdb):
     with open(PATH, "w") as f:
-        json.dump(pwdb, f)
+        f.write(json.dumps(pwdb))
+        f.write("\n")
+    f.close()
 
 
 def authenticate(username, password, pwdb):
     if username in pwdb:
         if password == pwdb[username]:
             print("Successfully authenticated!")
         else:
-            print("Wrong Password")
+            print("Wrong password")
     else:
         pwdb = add_user(username, password, pwdb)
         write_pwdb(pwdb)
+        print("New user added")
 
 def add_user(username, password, pwdb):
     pwdb[username] = password
     return pwdb
 
 username, password = get_credentials()
-pwdb = read_pwdb()
-authenticate(username, password, pwdb)
+pwdb = read_pwdb(username, password)