How to make connection string with python that has read only access?

I can Perform CRUD operations using Pymongo.
But I need only Retrieve not all operations.

How can I make that connection string?

Can you authenticate with a user that has read only access to the data?

I don’t know.
how can I authenticate a user who has read-only access to the cluster?
can we do that in https://cloud.mongodb.com/ ?

on the Atlas portal, go to Security-> Database Access, Add a new Database User, from there you can
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use one of the built-in roles called Only read any database or you can specify granular permissions by selecting “Grant specific privileges”