code with no tuple gets : IndexError: tuple index out of range

[Aggam]

Without the code, we can't help much. But the error suggests that one of those variables is a tuple and the index is too large.

Before the if you could print the types of them:

print(f"dataseg is of type {type(dataseg)} and has {len(dataseg)} elements.")
print(f"lines is of type {type(lines)} and has {len(lines)} elements.")

That won't tell you why you have a tuple, but it will tell you which one it is and its length.

I fixed i,Thanks for your help!