map_attributes.py

def dict_path(from_object, path):
    """
    >>> dict_path({'a': {'b': {'c': 123}}}, ['a', 'b'])
    {'c': 123}
    """
    if path == []:
        return from_object
    return dict_path(from_object[path[0]], path[1:])


def map_attributes(from_object, attribute_map):
    """
    >>> d = map_attributes({'a': {'b': {'c': 123}}}, {'a': 'a', 'b': 'a.b', 'c': 'a.b.c'})
    >>> d == {'a': {'b': {'c': 123}}, 'b': {'c': 123}, 'c': 123}
    True
    """
    r = {}

    for attr, key in attribute_map.items():
        key_path = key.split('.')
        r[attr] = dict_path(from_object, key_path)

    return r


if __name__ == '__main__':
    import doctest
    doctest.testmod()