def _value(self):
        """Get field value."""
        if self.data is not None:
            value = self.data._data.get(self.field.to_field.name)
            return str(value)
        return ''
def _value ( self ) : if self . data is not None : value = self . data . _data . get ( self . field . to_field . name ) return str ( value ) return ''
Get field value.