Working with django money and django graphene

type.py

import graphene
from graphene_django import DjangoObjectType

class Money(graphene.Scalar):
    @staticmethod
    def serialize(value):
        return value

    @staticmethod
    def parse_literal(node):
        return node

    @staticmethod
    def parse_value(value):
        return value

    @staticmethod
    def resolve(value):
        result = {
            'amount': 0,
            'currency': 'USD',
        }
        if value is None:
            return result

        result['currency'] = str(value.currency)

        try:
            result['amount'] = float(value.amount)
        except ValueError:
            return result

        return result
      
class ModelType(DjangoObjectType):
    cost = graphene.Field(Money)
    
     class Meta:
        name = 'model'
        model = Model
        interfaces = (graphene.relay.Node,)
        only_fields = [
            'id',
            'cost'
        ]
        filter_fields = [
            'id',            
        ]
    
    def resolve_cost(self, info):
        return Money.resolve(self.cost)