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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 changelist_view(self, request, extra_context=None):
 """ Get object currently tracked and add a button to get back to it """

        extra_context = extra_context or {}
        if 'object' in request.GET.keys():
            value = request.GET['object'].split(':')
            content_type = get_object_or_404(
                ContentType,
                id=value[0],
            )
            tracked_object = get_object_or_404(
                content_type.model_class(),
                id=value[1],
            )
            extra_context['tracked_object'] = tracked_object
            extra_context['tracked_object_opts'] = tracked_object._meta
        return super(TrackingEventAdmin, self).changelist_view(
            request, extra_context)