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 Management Settings.
To create a new Single* DocType, mark the **Is Single property as checked.
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