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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 supports(cls, *functionalities):
 """ A view decorator to indicate that an xBlock view has support for the given functionalities. Arguments: functionalities: String identifiers for the functionalities of the view. For example: "multi_device". """

        def _decorator(view):
            """
            Internal decorator that updates the given view's list of supported
            functionalities.
            """
            # pylint: disable=protected-access
            if not hasattr(view, "_supports"):
                view._supports = set()
            for functionality in functionalities:
                view._supports.add(functionality)
            return view
        return _decorator