def annotate(msg, geoc, filter_region=None):
    """
    Annotate message with geocountry info
    Params:
    msg - dict object
    geoc - GeoCountry object
    filter_region - region to be filtered
    """
    content = geoc.annotate(msg)
    content_region = content.get("embersGeoCodeCountry", {}).get("region", None)
    if content_region is None:
        return None

    if filter_region is not None and filter_region != content_region:
        return None

    return content