How to separate your VB.NET classes in different files

 Hi,
Currently in my ASP web page I have a single Default.aspx web file, which has a Default.aspx.vb file with code. 
Inside that Default.aspx.vb I have initially a main class, which looks like:

Partial Class _Default
   Inherits System.Web.UI.Page
...... 'My functions
End Class
 
But after that class, I have created a new one: 
Public Class MyClass
    'My methods
End Class
 
Both classes are in the same file, and I was wondering: is it possible to move "MyClass" to a separate file, and keep calling its methods from the Default class? 
Many thanks,
 
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