Accessing Functions defined in Modules under NET 4.5 Framework

Dear All,
I have been working with ASP.NET for some time now. However, my previous experience was with Framework 2.0 and 3.5. However, now I working on 4.5 Framework, wherein I would like to achieve the following:
I would like to define a function (public and shared) in a module and I would like to use/call the function (with or without overloading) and to get the result returned from the function. However, in the earlier versions, I used to use the code "Imports <module_name>" and after this the function was available in the whole web form / class.
But in 4.5, this usage is not being allowed. Kindly advise on how to achieve the same.  

Thanks
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