A python script produces an IFC-file wherein the following line appears several times:
PropertySingleValueWriter = ifcfile.createIfcPropertySingleValue("{}".format(V), "{}".format(k), ifcfile.create_entity("IfcText", str((val["{}".format(k)]))), None)
This produces (as one represantive example)
#598=IFCPROPERTYSINGLEVALUE('Object','Wall',IFCTEXT('12.3'),$);
The last argument None stands for the unit which, in this case, has not been given yet and was translated as $ in the output IFC-file. The unit known by line
#7=IFCSIUNIT(*,.LENGTHUNIT.,$,.METRE.);
in the IFC-file should now be inserted instead. This can be done manually in the IFC-file by writing #7 into the line,
#598=IFCPROPERTYSINGLEVALUE('Object','Wall',IFCTEXT('12.3'),#7);
Using an adapted python script would be much more efficient. However, I have not found the correct scripting yet to add #7 as a simple text. My attempts have been so far,
[1] PropertySingleValueWriter = ifcfile.createIfcPropertySingleValue("{}".format(V), "{}".format(k), ifcfile.create_entity("IfcText", str((val["{}".format(k)]))), "#7")
[2] PropertySingleValueWriter = ifcfile.createIfcPropertySingleValue("{}".format(V), "{}".format(k), ifcfile.create_entity("IfcText", str((val["{}".format(k)]))), "'#7'")
[3] PropertySingleValueWriter = ifcfile.createIfcPropertySingleValue("{}".format(V), "{}".format(k), ifcfile.create_entity("IfcText", str((val["{}".format(k)]))), "'{}'".format("#7"))
[4] PropertySingleValueWriter = ifcfile.createIfcPropertySingleValue("{}".format(V), "{}".format(k), ifcfile.create_entity("IfcText", str((val["{}".format(k)]))), ifcfile.create_entity("IfcText", "#7"))
They either produce an error ([1], [2], [3]) or explicitly write IFCTEXT('#7') ([4]) into the IFC-file which is not interpretable as a connection to the line #7.
Which is the correct scripting in the python file in order to get the connection to line #7 as achievable by manual editing?
You can use ifcfile.by_id(7)
so your code becomes
PropertySingleValueWriter = ifcfile.createIfcPropertySingleValue("{}".format(V), "{}".format(k), ifcfile.create_entity("IfcText", str((val["{}".format(k)]))), ifcfile.by_id(7))