the base from EntityDescriptor is undefined

[nao3301]

Error:
Object.defineProperty(this, 'entityID', { value: base.entityID });
^

TypeError: Cannot read property 'entityID' of undefined

File:
src/EntityDescriptor.js

Code:
module.exports = class EntityDescriptor {
constructor(metadata) {
console.log(metadata)
const base = metadata.EntityDescriptor;
console.log(base);
Object.defineProperty(this, 'entityID', { value: base.entityID });
Object.defineProperty(this, 'documentID', { value: base.ID });
}
};

metadata:
<md:EntityDescriptor ...

fix:

const base = metadata['md:EntityDescriptor'];