A application will usually have a Settings page. In our application, we can define a page where we can set the loan period. We also need to save this property. In Frappe, this can be done using a Single type DocType. A Single DocType is like the Singleton pattern in Java. It is an object with only one instance. Let us call this as Library Managment Settings.
To create an new Single DocType, mark the Is Single property as checked.
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