---
title: "What happens when you import a module? - Reuven M. Lerner"
tags: PyConTW2024, 2024-organize, 2024-共筆
---

# What happens when you import a module? - Reuven M. Lerner

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> Collaborative writing start from below
> 從這裡開始共筆

會議錄音、逐字稿、摘要與翻譯：https://s.dwave.cc/mkmvpjQ

## Simple case of ImportError when cyclic import happend

- `main.py`

import a
import b
if __name__ == '__main__':
    print("Hello world")

- `a.py`

from b import y
x = y

- `b.py`

from a import x
y = 1

Command

$ python -V
Python 3.12.4
$ python main.py
raceback (most recent call last):
  File "<File Path>/main.py", line 1, in <module>
    import a
  File "<File Path>/a.py", line 1, in <module>
    from b import y
  File "<File Path>/b.py", line 1, in <module>
    from a import x
ImportError: cannot import name 'x' from partially initialized module 'a' (most likely due to a circular import) (<File Path>/a.py)

Note that the raising error message had the keyword 'initialized' that means the error happen on loading module, which not on assign the module name.

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