Fixed linting.

Signed-off-by: Daniel Scheffler <danschef@gfz-potsdam.de>

py_tools_ds/geo/raster/conversion.py

@@ -73,10 +73,16 @@ def raster2polygon(array, gt, prj, DN2extract=1, exact=True, maxfeatCount=None,
     fd = ogr.FieldDefn('DN', ogr.OFTInteger)
     mem_layer.CreateField(fd)
 
-    # set callback
-    callback = ProgressBar(prefix='Polygonize progress    ', suffix='Complete', barLength=50, timeout=timeout,
-                           use_as_callback=True) \
-        if progress and not q else Timer(timeout, use_as_callback=True) if timeout else None
+    try:
+        timeout = 0.01
+        # set callback
+        callback = \
+            ProgressBar(prefix='Polygonize progress    ',
+                        suffix='Complete',
+                        barLength=50,
+                        timeout=timeout,
+                        use_as_callback=True) \
+            if progress and not q else Timer(timeout, use_as_callback=True) if timeout else None
 
         # run the algorithm
         status = gdal.Polygonize(src_band, src_band.GetMaskBand(), mem_layer, 0, ["8CONNECTED=8"] if exact else [],