How to access data via dot-notation

Goal: Pull video_id from assessment_obj, assign to variable
DB Type: SQLAlchemy
Model: Assessment holds video_id in a Many-to-One relationship (multiple assessments can use a video)

1.) I am trying to use dot.notation to pull the video_id from the assessment 2.) so that I can use the retrieve method to pull the video information (such as url).

Purpose: The video url will be used to enter into a video player src via a JINJA2 template/HTML code. (I apologize if I am using jargon incorrectly as I am new and am trying to better understand the concepts.)

I was trying to follow a OOP dot.notation tutorial, but was uncertain on how to pull the data from a table and assign to a variable without accidently reassigning the variable.

views.py
The form view config.

@view_config(route_name='save_assessment_result', renderer='templates/completedpage.jinja2')
def save_assessment_result(request):
    with transaction.manager:
        assessment_id = int(request.params['assessment_id'])
        assessment_obj = api.retrieve_assessment(assessment_id) # the assessment

        assessment_obj.video_id = video # this right? 
        thevid = api.retrieve_video(video) #retrieves the video via ID
        template_video = int(request.params['video'])
        # how do I get the retrieved video 'thevid' into the template? 

        # more code 

       transaction.commit()
       return HTTPCreated()

template: templates/assessment_form.jinja2

  <div class="embed-responsive embed-responsive-16by9">
    <iframe width="640" height="360" class="embed-responsive-item" allowfullscreen name='video' src="{{ url }}"></iframe>
  </div>

NEW: Return for assessment_obj. New View_Config.
Note: 'videoname': video.videoname, 'length': video.length, 'url': video.url

@view_config(route_name='assessment', request_method='GET', renderer='templates/assessment_form.jinja2')
def assessment_form_view(request):
    with transaction.manager:
        assessment_id = int(request.matchdict['id'])
        assessment = api.retrieve_assessment(assessment_id)
        if not assessment:
            raise HTTPNotFound()
        video_id = int(request.matchdict['id']) # <--- this gives the assessmnet_id and not the video
        video = api.retrieve_video(video_id)
        return {'assessment_id': assessment_id, 'assessment_name': assessment.name, 'assessment_text': assessment.text, 'user_id': assessment.user_id, 'video_id':assessment.video_id, 'categories': ','.join([str(i) for i in assessment.categories]), 'video_id':video_id, 'videoname': video.videoname, 'length': video.length, 'url': video.url}

Solution

In the line assessment_obj.video_id = video - where does the video variable come from?

Seeing that you're trying "pull the data from a table and assign to a variable" I'm wondering if you actually tried to assign assessment_obj.video_id to a variable called video. In this case it should be another way round:

video = assessment_obj.video_id

Then you code almost starts to make sense. To pass the data to the template you simply return a dictionary from your view function:

@view_config(route_name='save_assessment_result', renderer='templates/assessment_form.jinja2')
def save_assessment_result(request):
    with transaction.manager:
        assessment_id = int(request.params['assessment_id'])
        assessment_obj = api.retrieve_assessment(assessment_id) # the assessment

        video_id = assessment_obj.video_id
        thevid = api.retrieve_video(video_id)
        template_video = int(request.params['video'])
        return {
           'thevid': thevid,
           'template_video': template_video
        }

Then in your template you can reference those variables and their members:

<iframe ... src="{{ thevid.url }}"></iframe>