Help with extra work?

Hey, I know this isn’t part of the course but would it be possible for someone to give me a hand with whats wrong with this code?

def Nth_Value(Nth_term, Nth_value):
	n = Nth_value
	equation = "Nth_term",Nth_term.subs({"n", n})
	
sequence_or_relation = input("Do you want the next Nth Values or the Relationship in the sequence?(Nth Value/ Relationship)"
if sequence_or_relation == "Nth value":
	Un = input("What's the Nth Term?")
	n_v =input("What's the Nth Value?")
	Nth_Value(Un, n_v)
elif sequence_or_relation == Relationship:
	break

Now i know there may be other issues with this but at the moment I’m kinda stuck with a error that I cannot for the life of me understand,
Error:

Traceback (most recent call last):
  File "python", line 6
    if sequence_or_relation == "Nth value":
                                          ^
SyntaxError: invalid syntax

I’m sorta new to this and this is like my first attempt alone so sorry if there’s any glaring mistakes, I’m sorta just rolling with the errors

You get that error because of the line before that line

sequence_or_relation = input("Do you want the next Nth Values or the Relationship in the sequence?(Nth Value/ Relationship)")

you forgot the closing parenthesis

You will also get an error here

elif sequence_or_relation == Relationship:
	break

You can only use the break statement inside a loop

Also the string class has no attributed called subs as you use here