# A Weird Python Command Not Found Problem

## Problem Statement

I met a weird problem with the following output:

```shell-session
$ python
pyenv: python: command not found

The `python' command exists in these Python versions:
  3.9.11

Note: See 'pyenv help global' for tips on allowing both
      python2 and python3 to be found.
```

What happened??? I just took a nap and turned my computer back on, why did *python* get lost???

## Resolution

Ok... Let me check these paths: `/usr/bin` and `/usr/local/bin` :

```shell-session
$ ls /usr/bin /usr/local/bin | grep python
python3
```

OMG! ONLY `python3` EXISTS!

At that moment, I started to recall if I did anything stupid which removed the system `python` by mistake. 

After half an hour of useless attempts, it flashed through my mind that I had just upgraded to macOS Monterey 12.3.1 before I went to sleep, and let me check the [release notes](https://developer.apple.com/documentation/macos-release-notes/macos-12_3-release-notes#Python):

> #### Python <a href="#python" id="python"></a>
>
> **Deprecations**
>
> * Python 2.7 was removed from macOS in this update. Developers should use Python 3 or an alternative language instead. (39795874)

Now the truth is out, Apple took a shot at me.

This problem can be fixed simply as I have had another python3 installed by Homebrew.

```shell-session
$ brew install python3
-- snip --
Warning: python@3.9 3.9.12 is already installed and up-to-date.
To reinstall 3.9.12, run:
  brew reinstall python@3.9
```

And now you can simply create a symbolic link to it by:

```shell
sudo ln -s /opt/homebrew/bin/python3 /usr/local/bin/python
```

Finally, try `python` again:

```shell-session
$ python
Python 3.9.12 (main, Mar 26 2022, 15:44:31)
[Clang 13.1.6 (clang-1316.0.21.2)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> 
```

## Conclusion

Maybe I should read every release note carefully before I click *UPGRADE NOW.*

## Reference

1. [macOS Monterey 12.3 Release Notes](https://developer.apple.com/documentation/macos-release-notes/macos-12_3-release-notes#Python)


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