code: def get_rate_source():
      
      backend = money_rates_settings.DEFAULT_BACKEND()
      try:
          return RateSource.objects.get(name=backend.get_source_name())
      except RateSource.DoesNotExist:
          raise CurrencyConversionException(
              "Rate for %s source do not exists. "
              "Please run python manage.py update_rates" % backend.get_source_name())
docs: Get the default Rate Source and return it.