code: def convertShpToExtend(pathToShp):
       
      
      driver = ogr.GetDriverByName('ESRI Shapefile')
      dataset = driver.Open(pathToShp)
      if dataset is not None:
          # from Layer
          layer = dataset.GetLayer()
          spatialRef = layer.GetSpatialRef()
          # from Geometry
          feature = layer.GetNextFeature()
          geom = feature.GetGeometryRef()
          spatialRef = geom.GetSpatialReference()
          
          #WGS84
          outSpatialRef = osr.SpatialReference()
          outSpatialRef.ImportFromEPSG(4326)
  
          coordTrans = osr.CoordinateTransformation(spatialRef, outSpatialRef)
  
          env = geom.GetEnvelope()
  
          pointMAX = ogr.Geometry(ogr.wkbPoint)
          pointMAX.AddPoint(env[1], env[3])
          pointMAX.Transform(coordTrans)
          
          pointMIN = ogr.Geometry(ogr.wkbPoint)
          pointMIN.AddPoint(env[0], env[2])
          pointMIN.Transform(coordTrans)
  
  
          return [pointMAX.GetPoint()[1],pointMIN.GetPoint()[0],pointMIN.GetPoint()[1],pointMAX.GetPoint()[0]]
      else:
          exit(" shapefile not found. Please verify your path to the shapefile")
docs: reprojette en WGS84 et recupere l'extend