Error on ex13 (single linked list)

File “/Users/marcelo/python_repo_2019/project1/skeleton/TLL_container/TLL/”, 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

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

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.

class SingleLinkedListNode(object):

	def __init__(self, value, nxt):
		self.value = value = nxt
	def __repr__(self):
		nval = and 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."""