def has_og_property(meta_tag, properties):
    """
    Checks if the given meta tag has an attribute property equals to og:something,
    something being in properties.
    Returns:
        None if the given tag "is" not og:something. something otherwise.
    """
    try:
        if not meta_tag["property"].startswith("og:"):
            return None
        _property = meta_tag["property"][len("og:"):] # remove og: from beginning of tag
        if _property in properties:
            return _property
    except: # pylint: disable=bare-except
        pass
    return None