def transform_offer(offer):
    """
    Function to create a JSON from a single offer Object.
    Returns:
        [String]: JSON-String with fields for the parameter of the offer
    """
    return {
        'name': offer.name,
        'alias': offer.slug,
        'url': offer.url,
        'post': offer.post_data,
        'thumbnail': offer.thumbnail
    }