deduperreload gives invalid tracebacks in reloaded functions #15359

Python 3.13.14 | packaged by conda-forge | (main, Jun 12 2026, 09:50:25) [GCC 14.3.0]
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In [1]: %load_ext autoreload

In [2]: %autoreload -p 1

In [3]: %%writefile module.py
   ...: """
   ...: The traceback incorrectly points to this line (line 2 of the file)
   ...: """
   ...: def func():
   ...:     assert False, "before reload"
   ...:
   ...:

In [4]: %aimport module

In [5]: module.func()
---------------------------------------------------------------------------
AssertionError                            Traceback (most recent call last)
Cell In[5], line 1
----> 1 module.func()

File /tmp/module.py:5, in func()
      4 def func():
----> 5     assert False, "before reload"

AssertionError: before reload

In [6]: %%writefile module.py
   ...: """
   ...: The traceback incorrectly points to this line (line 2 of the file)
   ...: """
   ...: def func():
   ...:     assert False, "after reload"
   ...:
   ...:
Overwriting module.py

In [7]: module.func()
Reloading 'module'.
---------------------------------------------------------------------------
AssertionError                            Traceback (most recent call last)
Cell In[7], line 1
----> 1 module.func()

File /tmp/module.py:2, in func()
      1 """
----> 2 The traceback incorrectly points to this line (line 2 of the file)
      3 """
      4 def func():
      5     assert False, "after reload"

AssertionError: after reload