TypeError: key: expected bytes or bytearray, but got 'tuple'

[ndeoligence]

Issue:
Run the flask app (web/)
Click on the given link (http://127.0.0.1:5000) to access the app

Expected: Should show the img-upload page
Actual: Gives an error with this as part of the stacktrace (Only external files are shown in the stacktrace):

127.0.0.1 - - [01/Nov/2020 15:06:37] "GET / HTTP/1.1" 500 -
Traceback (most recent call last):
  File "ascii-art/venv/lib/python3.8/site-packages/flask/app.py", line 2464, in __call__
    return self.wsgi_app(environ, start_response)
  File "ascii-art/venv/lib/python3.8/site-packages/flask/app.py", line 2450, in wsgi_app
    response = self.handle_exception(e)
  File "ascii-art/venv/lib/python3.8/site-packages/flask/app.py", line 1867, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "ascii-art/venv/lib/python3.8/site-packages/flask/_compat.py", line 39, in reraise
    raise value
  File "ascii-art/venv/lib/python3.8/site-packages/flask/app.py", line 2446, in wsgi_app
    ctx.push()
  File "ascii-art/venv/lib/python3.8/site-packages/flask/ctx.py", line 390, in push
    self.session = session_interface.open_session(self.app, self.request)
  File "ascii-art/venv/lib/python3.8/site-packages/flask/sessions.py", line 348, in open_session
    data = s.loads(val, max_age=max_age)
  File "ascii-art/venv/lib/python3.8/site-packages/itsdangerous/timed.py", line 130, in loads
    base64d, timestamp = signer.unsign(s, max_age, return_timestamp=True)
  File "ascii-art/venv/lib/python3.8/site-packages/itsdangerous/timed.py", line 52, in unsign
    result = Signer.unsign(self, value)
  File "ascii-art/venv/lib/python3.8/site-packages/itsdangerous/signer.py", line 167, in unsign
    if self.verify_signature(value, sig):
  File "ascii-art/venv/lib/python3.8/site-packages/itsdangerous/signer.py", line 153, in verify_signature
    key = self.derive_key()
  File "ascii-art/venv/lib/python3.8/site-packages/itsdangerous/signer.py", line 132, in derive_key
    mac = hmac.new(self.secret_key, digestmod=self.digest_method)
  File "/usr/lib/python3.8/hmac.py", line 153, in new
    return HMAC(key, msg, digestmod)
  File "/usr/lib/python3.8/hmac.py", line 48, in __init__
    raise TypeError("key: expected bytes or bytearray, but got %r" % type(key).__name__)

[ndeoligence]

Solution: Remove the trailing comma from config.py:27

  SECRET_KEY = 'devlopment_key',

[rpdavila]

just fixed all of it