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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 wrap_once(self, LayoutClass, *args, **kwargs):
 """ Wraps every layout object pointed in `self.slice` under a `LayoutClass` instance with `args` and `kwargs` passed, unless layout object's parent is already a subclass of `LayoutClass`. """

        def wrap_object_once(layout_object, j):
            if not isinstance(layout_object, LayoutClass):
                layout_object.fields[j] = self.wrapped_object(
                    LayoutClass, layout_object.fields[j], *args, **kwargs
                )

        self.pre_map(wrap_object_once)