use markdown2, add forced login. Added breadcrumbs

captcha.py

@@ -1,20 +1,25 @@
 from random import randint
 import hashlib, base64
 
+
 # FIXME hash can be reused
 def generate(key):
-    '''
+    """
     Generate a simple CAPTCHA.
     It is based on a simple math expression which stops the simplest of bots.
-    '''
+    """
     # The parameters are chosen such that they are simple to solve on paper.
     a = randint(1, 10)
     b = randint(1, 10)
     c = randint(10, 20)
-    return f'{a} * {b} + {c} = ', _hash_answer(key, str(a * b + c))
+    return f"{a} * {b} + {c} = ", _hash_answer(key, str(a * b + c))
+
 
 def verify(key, answer, hash):
     return _hash_answer(key, answer) == hash
 
+
 def _hash_answer(key, answer):
-    return base64.b64encode(hashlib.sha256((key + answer).encode('utf-8')).digest()).decode('ascii')
+    return base64.b64encode(
+        hashlib.sha256((key + answer).encode("utf-8")).digest()
+    ).decode("ascii")