old_contents: from django.forms import ModelForm
  
  from .models import Client
  
  
  class ClientForm(ModelForm):
      class Meta:
          model = Client
          fields = (
              "name",
              "address_line_1",
              "address_line_2",
              "city",
              "postal_code",
              "country",
          )
  
new_contents: from django.forms import ModelForm
  
  from .models import Client
  
  
  class ClientForm(ModelForm):
      class Meta:
          model = Client
          fields = (
              "name",
              "address_line_1",
              "address_line_2",
              "city",
              "postal_code",
              "country",
              "organization",
          )
  
subject: Add the relationship field to the Client form