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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def register_viewer(self, vclass):
 """Register a channel viewer with the reference viewer. `vclass` is the class of the viewer. """

        self.viewer_db[vclass.vname] = Bunch.Bunch(vname=vclass.vname,
                                                   vclass=vclass,
                                                   vtypes=vclass.vtypes)