implemented dropdowns for fk fields in product and company admin

products/admin.py

@@ -1,5 +1,7 @@
 from django.contrib import admin
 
+from django_admin_listfilter_dropdown.filters import DropdownFilter, RelatedDropdownFilter, ChoiceDropdownFilter
+
 from . import models
 from . import forms
 
@@ -12,7 +14,13 @@ def model_admin_callable(co):
 class ProductAdmin(admin.ModelAdmin):
     form = forms.ProductTagForm
     list_display = ('name', 'category', 'sourcing_date', 'company', 'active' )
-    list_filter = ('company', 'tags', 'category', 'attributes')
+    list_filter = (
+        ('company', RelatedDropdownFilter),
+        ('tags', RelatedDropdownFilter),
+        ('category', RelatedDropdownFilter),
+        ('attributes', RelatedDropdownFilter)
+    )
+
     search_fields = ('name', 'sku', 'description')