Insert DataType using a custom dcdom 

Is it possible to insert a datatype using a custom dcdom? For example, I'm trying to insert the resource: https://w3id.org/wings/export/MINT#PIHMLandCover. 

The payload is:
```
{'parent_type': 'http://www.wings-workflows.org/ontology/data.owl#DataObject', 
'data_type': 'https://w3id.org/wings/export/MINT#PIHMLandCover'}
```
The result is:
```
OK
```

However, it is not created.