I have the same issue.

But I found Django reported the error, and asked me to add ALLOWED_HOST.

Here is the Django error report:

Starting development server at http://127.0.0.1:8000/

Quit the server with CONTROL-C.

Invalid HTTP_HOST header: 'm-s-2pg2b6emguv9.us-central1-c.c.codatalab-user-runtimes.internal:8007'. You may need to add 'm-s-2pg2b6emguv9.us-central1-c.c.codatalab-user-runtimes.internal' to ALLOWED_HOSTS.

Pay attention to the following: "You may need to add 'm-s-2pg2b6emguv9.us-central1-c.c.codatalab-user-runtimes.internal' to ALLOWED_HOSTS."

when I did this,

ALLOWED_HOSTS = ["colab.research.google.com",'m-s-2pg2b6emguv9.us-central1-c.c.codatalab-user-runtimes.internal']

it works.