[beginner] better-defaults not found

[<c.buhtz@posteo.jp>]

Hello at all,

I am a long year but low level vim user not moving to
emacs (primary for Python).

I tried to edit my ~/.emacs file (on Debian 10 stable) based on that
emacs-for-python-tutorial
https://realpython.com/emacs-the-best-python-editor/#initialization-file

When re-starting emacs I got the error that

/better-defaults-20170614.404.el, Not found

First of all I am confused about the version number because melpa.org
shows me "20200717.2012" for that package. I can understand that the
current package is not found. But I do not understand where the old
version number emacs using for this package comes from.

This is my .emacs (comment lines removed)

(when (>= emacs-major-version 24)
  (require 'package)
  (add-to-list
   'package-archives
    '("melpa" . "https://melpa.org/packages/")
   t))

(package-initialize)
(package-refresh-contents)
(defvar myPackages
  '(better-defaults
    material-theme
    )
  )

(mapc #'(lambda (package)
	  (unless (package-installed-p package)
	    (package-install package)))
      myPackages)