OSX - ZSH - PATH - /usr/bin duplicated
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I need some help to understand why my path looks like the way it looks.

Issuing echo $PATH in zsh returns :

    /Library/Frameworks/Python.framework/Versions/3.2/bin:/usr/bin/:/bin:/usr/sbin:/sbin:
    /usr/local/bin:/usr/X11/bin:/usr/local/go/bin:/usr/bin


Now, let's have a closer look of the different parts :

    - /Library/Frameworks/Python.framework/Versions/3.2/bin:

it comes from my .zprofile (Python 3 installation) 


    - /usr/bin/: 
    - /bin: 
    - /usr/sbin:
    - /sbin:
    - /usr/local/bin:

These parts come from my /etc/paths folder.

    - /usr/X11/bin:

This part come from my etc/path.d folder

    - /usr/local/go/bin:

This part was added during GO installation.

    - /usr/bin

???

I have looked at -/etc/paths -.zshrc -.zprofile -.profile -/etc/profile -.zshenv. 
None of them sourced or added a second /user/bin neither to the PATH.

How can I remove the second /user/bin from my PATH if I don't know which file to edit?

Thank you.
