Python - Como heredar y cambiar variables exportando en excel

def export_xls(modeladmin, request, queryset):

    import xlwt

    response = HttpResponse(content_type='application/ms-excel')

    response['Content-Disposition'] = 'attachment; filename=mimodelo.xls'

    wb = xlwt.Workbook(encoding='utf-8')

    ws = wb.add_sheet("MiModelo")

    columns = [

        (u"Nombre", 2000),

        (u"Apellido", 6000),

        ]

    row_num = 0

    font_style = xlwt.XFStyle()

    font_style.font.bold = True

    for col_num in xrange(len(columns)):

        ws.write(row_num, col_num, columns[col_num][0], font_style)

        # set column width

        ws.col(col_num).width = columns[col_num][1]

    font_style = xlwt.XFStyle()

    font_style.alignment.wrap = 1

    for obj in queryset:

        row_num += 1

        row = [

            obj.nombre,

            obj.apellido

        ]

        for col_num in xrange(len(row)):

            ws.write(row_num, col_num, row[col_num], font_style)

    wb.save(response)

    return response

def export_xls(modeladmin, request, queryset, columns, row):

# acá lo mismo...

# como ingresaría lo siguiente?:

def otro_export():???????????