code: def buildFileList(input, output=None, ivmlist=None,
                  wcskey=None, updatewcs=True, **workinplace):
      
      newfilelist, ivmlist, output, oldasndict, filelist = \
          buildFileListOrig(input=input, output=output, ivmlist=ivmlist,
                      wcskey=wcskey, updatewcs=updatewcs, **workinplace)
      return newfilelist, ivmlist, output, oldasndict
docs: Builds a file list which has undergone various instrument-specific
      checks for input to MultiDrizzle, including splitting STIS associations.