shell.FILEGROUPDESCRIPTORAsString

string = FILEGROUPDESCRIPTORAsString(descriptors, make_unicode )

Creates a FILEGROUPDESCRIPTOR from a sequence of mapping objects, each with FILEDESCRIPTOR attributes

Parameters

descriptors : [FILEDESCRIPTOR, ...]

A sequence of FILEDESCRIPTOR objects. Each filedescriptor object must be a mapping/dictionary, with the following optional attributes: dwFlags, clsid, sizel, pointl, dwFileAttributes, ftCreationTime, ftLastAccessTime, ftLastWriteTime, nFileSize If these attributes do not exist, or are None, they will be ignored - hence you only need specify attributes you care about.
In general, you can omit dwFlags - it will be set correctly based on what other attributes exist.

make_unicode=True : bool

If true, a FILEDESCRIPTORW object is created