/// <summary>
        /// Gets the URI of the part the element is in.
        /// </summary>
        /// <param name="element">The element.</param>
        /// <returns>The URI of the part the element is in. Returns null if not in a part.</returns>
        internal static Uri GetPartUri(this OpenXmlElement element)
        {
            var part = element.GetPart();

            if (part != null)
            {
                return(part.Uri);
            }

            return(null);
        }