如何从它的字符串引用中检索python对象

Question

I'm using Deform widgets to display an object's attribute. In my widget serialization method I can see that my cstruct is correct:

serialization cstruct: [<abc.modules.core.models.Assessment object at 0x105583320>]

When trying to display within jinja2 template the objet's property eg 'created_at' the result is:

jinja2.exceptions.UndefinedError: 'str object' has no attribute 'created_at'

What can I do to have the Assessment object considered as object and not as string within Jinja2? I believe it's very simple but I still can't find out what is wrong. Please help.

A bit more code: Schema node:

class SubcontractorAssessmentSchema(MappingSchema):
    """ **Schema definition for ``Subcontractor Assessment`` part.** """
    readonly = True
    assessments = SchemaNode(String(), widget=LastResultsWidget2(),
                             title='Assessment:', missing='')

[...]

Widget:

class LastResultsWidget2(SelectWidget):
    """ **Widget for Last Results.** """
    template = 'last_results'
    readonly_template = 'last_results'
    strip = True

    def serialize(self, field, cstruct, **kw):
        """
        Overwritten default serialize of SelectWidget.

        :param field: Field
        :param cstruct: Value of Widget
        :param kw: Additional arguments.
        :return: rendered field.
        """
        if cstruct in (colander.null, None):
            cstruct = self.null_value
#        print ('serialization cstruct: ' +str(cstruct))
        return field.renderer(self.template, field=field, cstruct=cstruct)

Answer 1

It was an error withi this certain Colader version. It was forcing the widget to behave singleton-like. Thank you for all your hints!