Problem accessing an aspx.vb/aspx.cs code behind file in the global website folder from a class in the App_Code folder, is this even possible?

I am trying to access a webform created in the global folder of the website from a class within the App_Code folder.

suppose class name is _Default;
the App_Code contains a class say SampleClass, I wanna add a reference to that webform in this class, for example:
Dim dflt As New _Default (VB)
_Default dflt = new _Default(); (CS)

 thanks 4 your time
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