build-system: pyproject: Normalize entry point import.

The standard is using from instead of import and it indeed allows to
avoid some side-effects in some cases, see
https://packaging.python.org/en/latest/specifications/entry-points/#use-for-scripts

* guix/build/pyproject-build-system (create-entrypoints)
[create-script]: Add -sP flags, improve pythonic style.

* gnu/packages/video.scm (python-yewtube)[arguments]<#:phases>: Remove
phase 'patch-script.

Change-Id: I995454c774666ed474b2418c18ec36c4f53bf015
Signed-off-by: Sharlatan Hellseher <sharlatanus@gmail.com>

gnu/packages/video.scm

@@ -6570,15 +6570,6 @@ can also directly record to WebM or MP4 if you prefer.")
           (add-before 'check 'configure-tests
             (lambda _
               (setenv "HOME" (getcwd))))
-          ;; XXX: This can happen when some side-effects happens at
-          ;; initialization. See https://codeberg.org/guix/guix/issues/1089
-          (add-before 'sanity-check 'patch-script
-            (lambda _
-              (substitute* (string-append #$output "/bin/.yt-real")
-                (("import mps_youtube as mod")
-                 "from mps_youtube.main import main")
-                (("sys\\.exit \\(mod\\.main\\.main \\(\\)\\)")
-                 "sys.exit(main())"))))
           (replace 'sanity-check
             (lambda _
               (invoke (string-append #$output "/bin/yt") "-h"))))))

guix/build/pyproject-build-system.scm

@@ -349,8 +349,8 @@ and return write it to PATH/NAME."
           (format port "#!~a
 # Auto-generated entry point script.
 import sys
-import ~a as mod
-sys.exit (mod.~a ())~%" interpreter module function)))
+from ~a import ~a
+sys.exit(~a())~%" interpreter module function function)))
       (chmod file-path #o755)))
 
   (let* ((site-dir (site-packages inputs outputs))