Hey @Seyf_Dardouri,
The mentors don’t have access to your Coursera Labs via Coursera. For sharing your notebook as an attachment, first you have to download your notebook, the instructions for which you can find listed as Method 1 in here. Once your notebook is downloaded, you can click on Balaji’s name and upload it as an attachment. I hope this helps.
P.S. - Sharing code publicly is strictly against the community guidelines, so please ensure that you DM your notebook.
Cheers,
Elemento