old_contents: from django import forms
  from django.utils.translation import ugettext_lazy as _
  
  from .models import Observer
  
  
  class ObserverForm(forms.ModelForm):
      first_name = forms.CharField(label=_("First name"), max_length=30, required=False)
      last_name = forms.CharField(label=_("Last name"), max_length=30, required=False)
  
      class Meta:
          model = Observer
          fields = ['first_name', 'last_name', 'aavso_code', 'limiting_magnitude', 'location']
  
      def __init__(self, *args, **kwargs):
          super(ObserverForm, self).__init__(*args, **kwargs)
          self.fields['first_name'].initial = self.instance.user.first_name
          self.fields['last_name'].initial = self.instance.user.last_name
  
      def save(self, *args, **kwargs):
          observer = super(ObserverForm, self).save(*args, **kwargs)
          observer.user.first_name = self.cleaned_data.get('first_name')
          observer.user.last_name = self.cleaned_data.get('last_name')
          observer.user.save()
          return observer
  
new_contents: from django import forms
  from django.utils.translation import ugettext_lazy as _
  
  from .models import Observer
  
  
  class ObserverForm(forms.ModelForm):
      first_name = forms.CharField(label=_("First name"), max_length=30, required=False)
      last_name = forms.CharField(label=_("Last name"), max_length=30, required=False)
  
      class Meta:
          model = Observer
          fields = ['first_name', 'last_name', 'aavso_code', 'limiting_magnitude', 'location', 'city']
  
      def __init__(self, *args, **kwargs):
          super(ObserverForm, self).__init__(*args, **kwargs)
          self.fields['first_name'].initial = self.instance.user.first_name
          self.fields['last_name'].initial = self.instance.user.last_name
  
      def save(self, *args, **kwargs):
          observer = super(ObserverForm, self).save(*args, **kwargs)
          observer.user.first_name = self.cleaned_data.get('first_name')
          observer.user.last_name = self.cleaned_data.get('last_name')
          observer.user.save()
          return observer
  
subject: Include city in ObserverForm.