How to use the qtawesome.load_font function in QtAwesome

def icon(name, scale_factor=None, resample=False, icon_path=None):
    theme = CONF.get('appearance', 'icon_theme')
    if theme == 'spyder 3':
        if not _resource['loaded']:
            qta.load_font('spyder', 'spyder.ttf', 'spyder-charmap.json',
                          directory=_resource['directory'])
            _resource['loaded'] = True
        args, kwargs = _qtaargs[name]
        if scale_factor is not None:
            kwargs['scale_factor'] = scale_factor
        return qta.icon(*args, **kwargs)
    elif theme == 'spyder 2':
        icon = get_icon(name + '.png', resample=resample)
        if icon_path:
            icon_path = osp.join(icon_path, name + '.png')
            if osp.isfile(icon_path):
                icon = QIcon(icon_path)
        return icon if icon is not None else QIcon()