/// <summary>
        /// Adds the specified list.
        /// </summary>
        /// <param name="list">The list.</param>
        public static void Add(List<ResumeField> list)
        {
            foreach (var item in list.SelectMany(item => item.Theme))
            {
                if (item == null ||
                    item.ResumeId < 1 ||
                    item.ThemeId < 1 ||
                    item.SkillId < 1)
                    throw new CustomException("Invalid part of resume","Add operation was broken by invalid argument");

                ResumeTheme.Add(item);
            }
            Context.SaveChanges();
        }