Using server response as foreign key table entry?

Question

I store a server response through a Y.io command with an on success that looks like this:

on: {
    success: function (requestId, response){
        sess_id = parseInt(response.responseText);
            buildtable();
    }               
}

buildtable() creates simulated data and uses the sess_id variable to fill in a column labeled session. This way every simulated data reading is associated with a session. my models for these two tables look like this:

class session(models.Model):
    start_time = models.IntegerField()
    end_time = models.IntegerField(null=True)

    def __unicode__(self):
        return unicode(self.pk)

class meterdata(models.Model):
    time_elapsed = models.FloatField()
    volts = models.FloatField()
    amps = models.FloatField()
    kW = models.FloatField()
    kWh = models.FloatField()
    session = models.ForeignKey(session)

    def __unicode__(self):
        return unicode(self.session)

when I try to store the simulated data into the meterdata table I get this error:

Cannot assign "5.0": "meterdata.session" must be a "session" instance

I have tried inserting it as a string, int, and float. I also am sure that there is actually a session created in the session table. How do i ensure the code understands that this number is referring to one of the ids in the session table?

edit: Here is the view that is being called when trying to save

@csrf_exempt
def save(request):
    if request.method == 'POST':
        rawdata1 = request.body
        rawdata2 = json.loads(rawdata1)
        for data in rawdata2:
            x = meterdata(time_elapsed = data['time_elapsed'], volts = data['volts'], amps = data['amps'], kW = data['kW'], kWh = data['kWh'], session = data['session'])
            x.save()        
        return HttpResponse(rawdata2)

Answer 1

Let me guess the value you put is the session id that's why the system telling you Cannot assign "5.0": "meterdata.session" must be a "session" instance. If this problem occur, telling about the instance, just add id in the variable to make it equal in your value like this session_id.

Other solution, so that you will not get that instance error, don't use the id.

Ex.

<select>
   {% for session in sessions %}
   <option value="{{ session }}">{{ session }}</option>
   {% endfor %}
</select>

As you noticed, I didn't use the session.id instead I use session only. This is the difference between instance and not instance.