implement password hashing function

auth.py

@@ -1,6 +1,7 @@
 import json
 import sys
 from getpass import getpass
+from hashlib import sha256
 
 PWDB_PATH = 'pwdb.json'
 
@@ -29,6 +30,9 @@ def write_pwdb(pwdb, PWDB_PATH):
     json.dump(pwdb, pwdb_file)
 
 
+def pwhash(pwd):
+    return sha256(pwd)
+
 if __name__ == "__main__":
     PWDB_PATH = 'pwdb.json'
     pwdb = read_pwdb(PWDB_PATH)