Workspace with chained loaders

>>> from woger import Workspace, BasePathStructure, BaseData
>>>
>>> class PathStructure(BasePathStructure):
...     json = 'json'
...     xml = 'xml'
>>>
>>> def load_json(data):
...     return '{}'
>>>
>>> def convert_to_xml(data):
...     return (
...         data.json
...         .replace('{', '<data>')
...         .replace('}', '</data>')
...     )
>>>
>>> class Data(BaseData):
...     json = load_json
...     xml = convert_to_xml
>>>
>>> ws = Workspace.construct('root', PathStructure, Data)
>>> print(ws.data.xml)
<data></data>