Where do frappe libraries/apps come from?

Going through tutorial Create a Site

It says bench --site library.test install-app library_management should install an application to existing site. However when I do that, I get python’s “ModuleNotFoundError: No module named ‘library_management’”.
Should I download something from somewhere to make things work? I honestly can’t understand if frappe libraries come from some repo, or from specific local directory

Did you create the library management app, as shown in the previous step?

https://frappeframework.com/docs/v14/user/en/tutorial/create-an-app

Hi,

In documentation, library.test is name of the site and library_management is a custom application for Library Management (To Manage the Books in Library, Membership of Library, and other functions) to demonstrate the capabilities of custom development of Frappe Framework.

If you do not create a library app in your development environment and try to install that application on the site will result in error.

If you want to learn the Frappe Development, better subtribe for this course on Frappe School: Frappe Framework Course

Courses on Frappe School are free of charge.

Thanks,

Divyesh Mangroliya