instruction:
In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.
question:
The zlib License is an open source software license .
answer:
The zlib license has been approved by the Free Software Foundation ( FSF ) as a free software license , and by the Open Source Initiative ( OSI ) as an open source license .


question:
Metro Vancouver is a regional district in British Columbia , Canada .
answer:
Metro Vancouver is a political body and corporate entity designated by provincial legislation as one of the regional districts in British Columbia , Canada .


question:
Archaeological evidence shows that Upper Egyptian culture replaced the Buto-culture at the delta when Upper and Lower Egypt were unified .
answer:

Archaeological evidence shows that Upper Egyptian culture replaced this Buto culture at the delta when Lower Egypt and Upper Egypt were unified , and the replacement is considered important evidence for the unification of the two portions of Ancient Egypt into one entity .