def opx_drop_all_except_active_sheet(wb, keep=[]):
    """Drop all worksheets except active one.
    
    Arguments:
        keep: List of exception sheetnames. All sheets on this list will not be dropped.
    """
    sheet_to_keep = [wb.active.title] + keep
    for sh in wb.sheetnames:
        if sh not in sheet_to_keep:
            del wb[sh]
    wb.active = 0
