human
Complete this python program:
def item_export_pdf():
assistant
#Here is the Python program you requested.

    """Export a list of Items in Adobe PDF format
    Uses Geraldo Grouping Report
    @ToDo: Use S3PDF Method
    """
    try:
        from reportlab.lib.units import cm
        from reportlab.lib.pagesizes import A4
        from reportlab.lib.enums import TA_CENTER, TA_RIGHT
    except ImportError:
        session.error = 'Python    needs    the    ReportLab    module    installed    for    PDF    export'
        redirect(URL(c='item'))
    try:
        from geraldo import Report, ReportBand, ReportGroup, Label, ObjectValue, SystemField, landscape, BAND_WIDTH
        from geraldo.generators import PDFGenerator
    except ImportError:
        session.error = 'Python    needs    the    Geraldo    module    installed    for    PDF    export'
        redirect(URL(c='item'))
    table = db.budget_item
    objects_list = db((table.id > 0)).select(orderby=table.category_type)
    if (not objects_list):
        session.warning = T('No    data    in    this    table    -    cannot    create    PDF!')
        redirect(URL(f='item'))
    import cStringIO
    output = cStringIO.StringIO()
    class MyReport(Report, ):
        def __init__(self, queryset=None, T=None):
            '    Initialise    parent    class    &    make    any    necessary    modifications    '
            Report.__init__(self, queryset)
            self.T = T
        def _T(self, rawstring):
            return self.T(rawstring)
        title = 'Items'
        page_size = landscape(A4)
        class band_page_header(ReportBand, ):
            height = (1.3 * cm)
            elements = [SystemField(expression='%(report_title)s', top=(0.1 * cm), left=0, width=BAND_WIDTH, style={'fontName': 'Helvetica-Bold', 'fontSize': 14, 'alignment': TA_CENTER}), Label(text='Code', top=(0.8 * cm), left=(0.2 * cm)), Label(text='Description', top=(0.8 * cm), left=(3 * cm)), Label(text='Unit    Cost', top=(0.8 * cm), left=(13 * cm)), Label(text='per    Month', top=(0.8 * cm), left=(15 * cm)), Label(text='per    Minute', top=(0.8 * cm), left=(17 * cm)), Label(text='per    Megabyte', top=(0.8 * cm), left=(19 * cm)), Label(text='Comments', top=(0.8 * cm), left=(21 * cm))]
           ...