fix many implicit ifcopenshell.guid imports

a bit related to 10d30b0de

src/blenderbim/scripts/classifications/xml_classification.py

@@ -4,6 +4,7 @@
 
 import xml.etree.ElementTree as ET
 import ifcopenshell
+import ifcopenshell.guid
 import os
 
 class IFC4Extractor:

src/blenderbim/scripts/dxf2ifc.py

@@ -17,6 +17,7 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.guid
 import ezdxf
 
 

src/blenderbim/scripts/obj2ifc-meshlab.py

@@ -23,6 +23,7 @@ import pymeshlab
 import ifcopenshell
 import ifcopenshell.api
 import ifcopenshell.api.owner.settings
+import ifcopenshell.guid
 from pathlib import Path
 
 import numpy as np

src/blenderbim/scripts/obj2ifc.py

@@ -23,6 +23,7 @@ import pywavefront
 import ifcopenshell
 import ifcopenshell.api
 import ifcopenshell.api.owner.settings
+import ifcopenshell.guid
 from pathlib import Path
 
 import numpy as np