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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 editpermissions_group_view(self, request, group_id, forum_id=None):
 """ Allows to edit group permissions for the considered forum. The view displays a form to define which permissions are granted for the given group for the considered forum. """

        group = get_object_or_404(Group, pk=group_id)
        forum = get_object_or_404(Forum, pk=forum_id) if forum_id else None

        # Set up the context
        context = self.get_forum_perms_base_context(request, forum)
        context['forum'] = forum
        context['title'] = '{} - {}'.format(_('Forum permissions'), group)
        context['form'] = self._get_permissions_form(
            request, GroupForumPermission, {'forum': forum, 'group': group},
        )

        return render(request, self.editpermissions_group_view_template_name, context)