Error on ex13 (single linked list)

Python
#1

File “/Users/marcelo/python_repo_2019/project1/skeleton/TLL_container/TLL/game.py”, line 8
return f"[{self.value}:{repr(nval)}]"
^
SyntaxError: invalid syntax
I have tried 15 different ways and it’s not working.
I am using this env:
Python 3.6.5

#2

That line on its own looks good to me. Can you post the whole function?

#3

Remember that errors can be on that line or any line above it. Check indentation, missing double or single quotes, missing parenthesis, on the lines above that line.

#4 
class SingleLinkedListNode(object):

	def __init__(self, value, nxt):
		self.value = value
		self.next = nxt
	def __repr__(self):
		nval = self.next and self.next.value or None
		return (f"{self.value}:{repr(nval)}")


```class SingleLinkedList(object):

	def __init__(self):
		self.begin = None
		self.end = None
	def push(self, obj):
		"""Appends a new value on the end of the list."""