I don’t understand where the error is

 pricexls['Price'] = [y['Zakup'] if x['Nac1'] == 1 else z['Price'] for x,y,z in zip(pricexls['Nac1'] , pricexls['Zakup'], pricexls['Price'])]

▼ Local vars
Variable    Value
.0  
<zip object at 0x000>
x   
0.0
y   
796.0
z   
940.0

swears at the value of x