code: def renders(col_name):
      
  
      def wrap(f):
          if not hasattr(f, '_col_name'):
              f._col_name = col_name
          return f
  
      return wrap
docs: Use this decorator to map your custom Model properties to actual
          Model db properties. As an example::
  
              class MyModel(Model):
                  id = Column(Integer, primary_key=True)
                  name = Column(String(50), unique = True, nullable=False)
                  custom = Column(Integer(20))
  
                  @renders('custom')
                  def my_custom(self):
                      # will render this columns as bold on ListWidget
                      return Markup('<b>' + custom + '</b>')
  
              class MyModelView(ModelView):
                  datamodel = SQLAInterface(MyTable)
                  list_columns = ['name', 'my_custom']