public override AccountNrOfContactsSetEvent Execute(SetAccountNrOfContactsCommand command)
        {
            command.FromContact = command.FromContact ?? throw new ArgumentNullException(nameof(command.FromContact));

            if (command.FromContact.ParentCustomerId == null)
            {
                return(null);
            }

            int nrOfContacts = accountQueries.GetNrOfContacts(command.FromContact.ParentCustomerId.Id);

            Account account = new Account
            {
                Id   = command.FromContact.ParentCustomerId.Id,
                Name = $"I have {nrOfContacts} contacts"
            };

            OrgServiceWrapper.OrgServiceAsSystem.Update(account);

            return(new AccountNrOfContactsSetEvent {
                TargetContact = command.FromContact
            });
        }