After Edebug:
I found the problem location:

  - [ ] org-babel-execute:python

    #+begin_src emacs-lisp
    (session (org-babel-python-initiate-session
              (cdr (assq :session params))))
    #+end_src

    - [ ] org-babel-python-initiate-session
      - [ ] org-babel-python-session-buffer

BTW: I'm using latest `master` branch source code.

[stardiviner]           <Hack this world!>      GPG key ID: 47C32433
IRC(freeenode): stardiviner                     Twitter:  @numbchild
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Blog: http://stardiviner.github.io/

On Fri, Dec 29, 2017 at 7:28 PM, Nicolas Goaziou <mail@nicolasgoaziou.fr>
wrote:

> Hello,
>
> stardiviner <numbchild@gmail.com> writes:
>
> > I have following org content:
> >
> > I define variable in Python inferior REPL (launched by [M-x run-python])
> >
> > Python> name = "chris"
> >
> > #+begin_src python :session "*Python*"
> > print(name)
> > #+end_src
> >
> > But I got error:
> >
> >  > org-babel-python-evaluate-session: Buffer *Python-*Python** does not
> > exist or has no process
>
> Try this:
>
>     #+begin_src python :session *Python* :results output
>     print(name)
>     #+end_src
>
>     #+RESULTS:
>     : chris
>
>
> Regards,
>
> --
> Nicolas Goaziou
>