🕵️ Stack Trace Lineup

from typing import NamedTuple

class Point(NamedTuple):
    x: int
    y: int

p = Point(1, 2)
p.x = 99

Traceback (most recent call last):
  File "lineup.py", line 7, in <module>
    p.x = 99
    ^^^
AttributeError: can't set attribute

import sys
sys.setrecursionlimit(40)
def f(): f()
try:
    f()
except RecursionError as e:
    print("ok", type(e).__name__)

# (no error in main — the RecursionError IS caught)
ok RecursionError

class Vec:
    __slots__ = ("x", "y")

Vec.z = 99
print(Vec.z)

Traceback (most recent call last):
  File "lineup.py", line 4, in <module>
    Vec.z = 99
SlotsViolationError: cannot add 'z' to slotted class 'Vec'

from abc import ABC, abstractmethod

class Animal(ABC):
    @abstractmethod
    def speak(self): ...

Animal()

Traceback (most recent call last):
  File "lineup.py", line 7, in <module>
    Animal()
    ~~~~~~^^
TypeError: Can't instantiate abstract class Animal without an implementation for abstract method 'speak'

import itertools
result = list(itertools.islice(itertools.cycle([1, 2]), 5))
print(result)

# (no error)
[1, 2, 1, 2, 1]