Issues with exported ontology XML if entity IRIs use "/" instead of "#"

First of all, a fantastic tool!

I played with it today making ontology.

I noticed issues in generated ontology if I use "/" instead of "#" for entities IRIs.

Code for IRIs which use "/":

onto = get_ontology("http://knowledge.graph/wind/")
define_datatype_in_ontology(VestasNaming, "http://knowledge.graph/wind/VestasNaming", onto)

class DO(Thing):
    namespace = onto

class notation(Thing >> VestasNaming):
    namespace = onto

HorWdSpd = DO("HorWdSpd", namespace = onto, 
              label="Horizontal Wind Speed", 
              comment="IEC data object instance for Horizontal Wind Speed")

HorWdSpd.notation.append(VestasNaming("WindSpeed"))

onto.save("./ontology.xml")

which results in

<?xml version="1.0"?>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
         xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
         xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
         xmlns:owl="http://www.w3.org/2002/07/owl#"
         xmlns:wind="http://knowledge.graph/wind/"
         xmlns="http://knowledge.graph/wind/">

<owl:Ontology rdf:about="http://knowledge.graph/wind"/>

<owl:DatatypeProperty rdf:about="notation">
  <rdfs:domain rdf:resource="http://www.w3.org/2002/07/owl#Thing"/>
  <rdfs:range rdf:resource="VestasNaming"/>
</owl:DatatypeProperty>

<owl:Class rdf:about="DO">
  <rdfs:subClassOf rdf:resource="http://www.w3.org/2002/07/owl#Thing"/>
</owl:Class>

<rdfs:Datatype rdf:about="VestasNaming"/>

<wind:DO rdf:about="HorWdSpd">
  <rdf:type rdf:resource="http://www.w3.org/2002/07/owl#NamedIndividual"/>
  <rdfs:label rdf:datatype="http://www.w3.org/2001/XMLSchema#string">Horizontal Wind Speed</rdfs:label>
  <rdfs:comment rdf:datatype="http://www.w3.org/2001/XMLSchema#string">IEC data object instance for Horizontal Wind Speed</rdfs:comment>
  <wind:notation rdf:datatype="VestasNaming">WindSpeed</wind:notation>
</wind:DO>

</rdf:RDF>

which when loaded to Protege results in two DO classes instead of one. One of those DO classes has correct IRI but no instances/individuals, the second one with an IRI equal to the filepath to onotology (obviously worng IRI) has a HorWdSpd individual related to it.

However, if I use "#" instead for IRI entities (i.e., base_iri#ClassName):

onto = get_ontology("http://knowledge.graph/wind")
define_datatype_in_ontology(VestasNaming, "http://knowledge.graph/wind#VestasNaming", onto)

class DO(Thing):
    namespace = onto

class notation(Thing >> VestasNaming):
    namespace = onto

HorWdSpd = DO("HorWdSpd", namespace = onto, 
              label="Horizontal Wind Speed", 
              comment="IEC data object instance for Horizontal Wind Speed")

HorWdSpd.notation.append(VestasNaming("WindSpeed"))

onto.save("./ontology.xml")

everything works as expected and resulting XML is correct:

<?xml version="1.0"?>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
         xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
         xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
         xmlns:owl="http://www.w3.org/2002/07/owl#"
         xml:base="http://knowledge.graph/wind"
         xmlns="http://knowledge.graph/wind#">

<owl:Ontology rdf:about="http://knowledge.graph/wind"/>

<owl:DatatypeProperty rdf:about="#notation">
  <rdfs:domain rdf:resource="http://www.w3.org/2002/07/owl#Thing"/>
  <rdfs:range rdf:resource="#VestasNaming"/>
</owl:DatatypeProperty>

<owl:Class rdf:about="#DO">
  <rdfs:subClassOf rdf:resource="http://www.w3.org/2002/07/owl#Thing"/>
</owl:Class>

<rdfs:Datatype rdf:about="#VestasNaming"/>

<DO rdf:about="#HorWdSpd">
  <rdf:type rdf:resource="http://www.w3.org/2002/07/owl#NamedIndividual"/>
  <rdfs:label rdf:datatype="http://www.w3.org/2001/XMLSchema#string">Horizontal Wind Speed</rdfs:label>
  <rdfs:comment rdf:datatype="http://www.w3.org/2001/XMLSchema#string">IEC data object instance for Horizontal Wind Speed</rdfs:comment>
  <notation rdf:datatype="#VestasNaming">WindSpeed</notation>
</DO>

</rdf:RDF>

which when loaded in Protege result in a single class DO, and HorWdSpd instance of it.

Is there anything I should do to make sure that entity IRIs which use "/" work properly when ontology is exported to XML?

pwin / owlready2

Issues with exported ontology XML if entity IRIs use "/" instead of "#" #20