SheetSet class

Describes a set of sheets.

The SheetSet type exposes the following members:

Constructor	Description
`__init__(self, sheet_indexes)`	Creates a sheet set based on exact sheet indexes.
`__init__(self, sheet_names)`	Creates a sheet set based on exact sheet names.

Property	Description
active	Gets a set with active sheet of the workbook.
visible	Gets a set with visible sheets of the workbook in their original order.
all	Gets a set with all sheets of the workbook in their original order.