Global code to center user forms

I have the following code which centers user forms on their screen, i have this in every module (with a different form name of course), but would like to simlyfy it into a global module and just call it from each form when it initialises.

Private Sub UserForm_Initialize()

With frm_About
    .StartUpPosition = 0
    .Left = Application.Left + (0.5 * Application.Width) - (0.5 * .Width)
    .Top = Application.Top + (0.5 * Application.Height) - (0.5 * .Height)
    .Show
End With

End Sub

I was thinking something along the lines of storing the form name as a varaible (strFrmName) and then using code as such :

PrFunstion Center_UserForm()

With strFrmName
    .StartUpPosition = 0
    .Left = Application.Left + (0.5 * Application.Width) - (0.5 * .Width)
    .Top = Application.Top + (0.5 * Application.Height) - (0.5 * .Height)
    .Show
End With

End Sub

But its not working. I have also tried the below with no luck. Icannot find anythin online about this either:

With vba.userforms(strFrmName)