Arch: add missing import, fixes regression added with commit c7d0cf044c

src/Mod/Arch/importIFCHelper.py

@@ -27,8 +27,12 @@ import FreeCAD
 import Arch
 import ArchIFC
 
+if FreeCAD.GuiUp:
+    import FreeCADGui as Gui
+
 from draftutils.messages import _msg, _wrn
 
+
 PREDEFINED_RGB = {"black": (0, 0, 0),
                   "red": (1.0, 0, 0),
                   "green": (0, 1.0, 0),