'unsupported operand type(s) for -: 'decimal.Decimal' and 'float' in Python 3

I am getting this issue unsupported operand type(s) for -: 'decimal.Decimal' and 'float'

Here is my models.py

def _convert(self,from_currency, to_currency, price):
        custom_rate_obj = self.quote.client.custom_rates.filter(currency=to_currency).first()
        if custom_rate_obj is None or custom_rate_obj.exchange_rate in (0, None):
            custom_rate_obj = ExchangeRates.objects.latest('created')
        return custom_rate_obj.convert(from_currency, to_currency, price)

    def get_margin(self):
        if self.cost_price:
            cost_price = self.cost_price
            unit_price = self._convert(self.currency, self.cost_currency, self.unit_price)
            if unit_price:
                return ((unit_price - float(cost_price))/unit_price) * 100

How can i solve my issue

Solution 1:^[1]

Change the unit_price to float as well.

 return ((float(unit_price) - float(cost_price))/unit_price) * 100

And always use typing in python 3 t avoid such errors.

def _convert(self,from_currency: str, to_currency : str, price: float) => float:

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution	Source
Solution 1	Rama

'unsupported operand type(s) for -: 'decimal.Decimal' and 'float' in Python 3

Solution 1:[1]

Sources

Related Questions

Solution 1:^[1]