The following methods aren't covered yet:
LexemeForm
- toJSON
- _normalizeData
- get
- edit_elements
LexemeSubEntity
- _ _init_ _
- fromJSON
- toJSON
- on_lexeme
- addClaim
- removeClaims
LexemePage
- _ _init_ _
- toJSON
- get
- normalizeData
- add_form
- remove_form
- mergeInto
- isRedirectPage