index 1 out of range for positional args tuple

Question

I'm trying to print the following line, which is part of an auxiliary classifier GAN code:

print('{0:<22s} | {1:15s} | {2:15s} | {3:5s}'.format('component', *discriminator.metrics_names))

but it results in this error:

IndexError: Replacement index 1 out of range for positional args tuple