Update skrf/vectorFitting.py
@@ -1875,7 +1875,7 @@ class VectorFitting:
for n in range(self.network.nports):
str_input_nodes += 'p{} '.format(n + 1)
- f.write('.SUBCKT {} {}\n'.format(fitted_model_name, str_input_nodes))
+ f.write(f'.SUBCKT {fitted_model_name} {str_input_nodes}\n')
for n in range(self.network.nports):
f.write('*\n')
