docs: def delete_templatetype(type_id,template_i=None, **kwargs):
      """
          Delete a template type and its typeattrs.
      """
      try:
          tmpltype_i = db.DBSession.query(TemplateType).filter(TemplateType.id == type_id).one()
      except NoResultFound:
          raise ResourceNotFoundError("Template Type %s not found"%(type_id,))
  
      if template_i is None:
          template_i = db.DBSession.query(Template).filter(Template.id==tmpltype_i.template_id).one()
  
      template_i.templatetypes.remove(tmpltype_i)
  
      db.DBSession.delete(tmpltype_i)
      db.DBSession.flush()