feat(api): implemented create sale as api endpoint.

tienda_ilusion/don_confiao/serializers.py

@@ -0,0 +1,17 @@
+from rest_framework import serializers
+
+from .models import Sale, SaleLine
+
+
+class SaleLineSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = SaleLine
+        fields = ['id', 'sale', 'product', 'unit_price', 'quantity']
+
+
+class SaleSerializer(serializers.ModelSerializer):
+    lines = SaleLineSerializer(many=True)
+
+    class Meta:
+        model = Sale
+        fields = ['id', 'customer', 'date', 'lines']