forward_attrs_to_dict.py

def _forward_attr_to_dict(cls, target, field):
    _property = property( \
        lambda obj: getattr(obj, target)[field],
        lambda obj, value: getattr(obj, target).__setitem__(field, value))
    setattr(cls, field, _property)

def _forward_attrs_to_dict(cls, target, fields=[]):
    for field in fields:
        _forward_attr_to_dict(cls, target, field)
    return cls

def forward_attrs_to_dict(target, fields):
    return lambda cls: _forward_attrs_to_dict(cls, target, fields)