Render dict from Django model

utils.py

def render_dict(pattern, data):
    """Render Django model to dict (helps in rendering JSON)"""
    out = {}
    for item in pattern:
        if isinstance(item, basestring):
            attr = manager_getattr(data, item)
            out[item] = attr
        elif isinstance(item, dict):
            for subitem, subpattern in item.items():
                attr = manager_getattr(data, subitem)
                out[subitem] = render_dict(subpattern, attr)
        else:
            if len(item) == 2:
                subitem, subpattern = item
                subdata = manager_getattr(data, subitem)
            else:
                subitem, custom_getattr, subpattern = item
                subdata = custom_getattr(data)
            out[subitem] = [render_dict(subpattern, d) for d in subdata]
    return out


# helpers
def smart_getattr(obj, attr_name):
    attr = getattr(obj, attr_name)
    if callable(attr):
        attr = attr()
    return attr

def manager_getattr(obj, attr_name):
    attr = smart_getattr(obj, attr_name)
    if isinstance(attr, models.Manager):
        attr = attr.all()
    return attr