Error to manage when trying to create a competition without any existing gym

[scorreia]

Start the application for the very time (no data created)
Login and create a new competition (without having first created a gym).

then, we get this error:
Traceback (most recent call last):
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/app.py", line 2463, in call
return self.wsgi_app(environ, start_response)
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/app.py", line 2449, in wsgi_app
response = self.handle_exception(e)
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/app.py", line 1866, in handle_exception
reraise(exc_type, exc_value, tb)
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/_compat.py", line 39, in reraise
raise value
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/app.py", line 2446, in wsgi_app
response = self.full_dispatch_request()
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/app.py", line 1951, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/app.py", line 1820, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/_compat.py", line 39, in reraise
raise value
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/app.py", line 1949, in full_dispatch_request
rv = self.dispatch_request()
File "/Users/scorreia/devel/git/skala3ma/.venv/lib/python3.11/site-packages/flask/app.py", line 1935, in dispatch_request
return self.view_functionsrule.endpoint
File "/Users/scorreia/devel/git/skala3ma/competitionsApp.py", line 163, in decorated_function
return fn(*args, **kwargs)
File "/Users/scorreia/devel/git/skala3ma/competitionsApp.py", line 693, in new_competition_post
competitionId = competitionsEngine.addCompetition(None, name, date, routesid, max_participants)
File "/Users/scorreia/devel/git/skala3ma/competitionsEngine.py", line 149, in addCompetition
competition = {"id": compId, "name": name, "date": date, "gym": gym['name'],"gym_id":gym['id'],