python - Create polygon from OGREnvelope

I have a folder full of about 2000 files and I would like to generate a kind of key map for each file so people don't need to just randomly load each one in order to find what is what.

I have the following python code using ogr but OGREnvelope isn't really a OGRGeometry so I can't add it to a shape file or export it as wkt to import in QGIS.

for filename in glob.glob(path + "*.shp"):
   ds = ogr.Open(filename)

   layer1 = ds.GetLayer(0)
   #print filename + " : " + str(layer1.GetExtent())
   extent = layer1.GetExtent()
   # I need to be able to export the extent region as a polygon.

I have been looking around but just can't seem to find anything. I really thought something like this would be easy.

Answer

You can make your own WKT from this. You can try adding something like this to your code.

print 'POLYGON((' \
          + str(extent[0]) + ' ' + str(extent[1]) + ', ' \

          + str(extent[0]) + ' ' + str(extent[3]) + ', ' \
          + str(extent[2]) + ' ' + str(extent[3]) + ', ' \
          + str(extent[2]) + ' ' + str(extent[1]) + ', ' \
          + str(extent[0]) + ' ' + str(extent[1]) + '))'