Correct errors

app/models/attachement.py

@@ -22,11 +22,11 @@ class Attachement(db.Model):
     def __init__(self, file, comment):
         self.name = file.filename
         self.size = os.stat(file).st_size
-        self.hashed = str(hash_file(file))
+        self.hashed = hash_file(file)
         self.comment = comment
 
     def hash_file(file):
         with open(file,"rb") as f:
             bytes = f.read() # read entire file as bytes
-            hashed = hashlib.sha256(bytes).hexdigest()
+            hashed = sha256(bytes).hexdigest()
         return hashed