When having an observable property with data type of DataTypeIdentifier, the DataType is not imported into XXX_base.py

Minimal code example, with the entire body of the sila.xml file as:

  <Property>
    <Identifier>Status</Identifier>
    <DisplayName>Status</DisplayName>
    <Description>Status of the currently running sampleset</Description>
    <Observable>Yes</Observable>
    <DataType>
      <List>
        <DataType>
          <DataTypeIdentifier>HplcResultReference</DataTypeIdentifier>
        </DataType>
      </List>
    </DataType>
  </Property>


  <DataTypeDefinition>
    <Identifier>HplcResultReference</Identifier>
    <DisplayName>HPLC Result Reference</DisplayName>
    <Description>Information about the result of an injection</Description>
    <DataType>
      <Basic>String</Basic>
    </DataType>
  </DataTypeDefinition>

After running sila2-codegen.exe generate-feature-files, HplcResultReference is used in XXX_base.py without being imported from XXX_types.py.

The server can be started, so I don't think it is results in an error, though I have only done minimal testing.