InMemoryUploadedFile is not JSON serializable

I'm sending a payload with some string and two images in a POST Request. But I'm not sure how to serialize the images in the payload. I'm using POSTMAN's form-data to send this request and I'm getting ('Object of type InMemoryUploadedFile is not JSON serializable')

def registration(self, payload):
    try:
        headers = {"accept": "application/json"}
        logger.debug({"payload": payload})
        response = requests.post(url=self.registration_url, headers=headers,json=payload)

        if response is None:
            return None, status.HTTP_424_FAILED_DEPENDENCY

        parsed_data = data_parser.render_registration_response(response, payload)
        return parsed_data, response.status_code

    except Exception as e:
        logger.error(repr(e))
        return None, status.HTTP_424_FAILED_DEPENDENCY

Serializers.py

class RegistrationSerializer(serializers.Serializer):
     name = serializers.CharField(max_length=20)
     vehicle_number = serializers.CharField(max_length=50)
     blue_book = serializers.ImageField(max_length=None, allow_empty_file=False, required=False)
     vehicle_class = serializers.CharField(max_length=50)
     bank_account = serializers.CharField(max_length=50)
     phone = serializers.CharField(max_length=20)
     avatar = serializers.ImageField(max_length=None, allow_empty_file=False, required=False)
     country = serializers.CharField(max_length=20)
     state = serializers.CharField(max_length=20)
     city = serializers.CharField(max_length=20)
     zip = serializers.CharField(max_length=20)