addon manager: use get_python_exe from utils file

src/Mod/AddonManager/AddonManagerOptions.ui

@@ -270,38 +270,6 @@ installed addons will be checked for available updates
    </item>
    <item>
     <layout class="QGridLayout" name="gridLayout">
-     <item row="0" column="0">
-      <widget class="QLabel" name="fclabel">
-       <property name="text">
-        <string>Path to Python executable (optional):</string>
-       </property>
-      </widget>
-     </item>
-     <item row="0" column="1">
-      <widget class="Gui::PrefFileChooser" name="gui::preffilechooser" native="true">
-       <property name="sizePolicy">
-        <sizepolicy hsizetype="Expanding" vsizetype="Preferred">
-         <horstretch>0</horstretch>
-         <verstretch>0</verstretch>
-        </sizepolicy>
-       </property>
-       <property name="minimumSize">
-        <size>
-         <width>300</width>
-         <height>0</height>
-        </size>
-       </property>
-       <property name="toolTip">
-        <string>The path to the Python executable for package installation with pip. Autodetected if needed and not specified.</string>
-       </property>
-       <property name="prefEntry" stdset="0">
-        <cstring>PythonExecutableForPip</cstring>
-       </property>
-       <property name="prefPath" stdset="0">
-        <cstring>Addons</cstring>
-       </property>
-      </widget>
-     </item>
      <item row="1" column="0">
       <widget class="QLabel" name="label_3">
        <property name="text">

src/Mod/AddonManager/addonmanager_dependency_installer.py

@@ -27,6 +27,8 @@ import os
 import subprocess
 from typing import List
 
+from freecad.utils import get_python_exe
+
 import addonmanager_freecad_interface as fci
 from addonmanager_pyside_interface import QObject, Signal, is_interruption_requested
 
@@ -170,7 +172,7 @@ class DependencyInstaller(QObject):
 
     def _get_python(self) -> str:
         """Wrap Python access so test code can mock it."""
-        python_exe = utils.get_python_exe()
+        python_exe = get_python_exe()
         if not python_exe:
             self.no_python_exe.emit()
         return python_exe

src/Mod/AddonManager/addonmanager_devmode.py

@@ -29,6 +29,7 @@ import subprocess
 
 import FreeCAD
 import FreeCADGui
+from freecad.utils import get_python_exe
 
 from PySide.QtWidgets import (
     QFileDialog,
@@ -618,7 +619,7 @@ class DeveloperMode:
             FreeCAD.Console.PrintMessage(
                 translate("AddonsInstaller", "Attempting to install Vermin from PyPi") + "...\n"
             )
-            python_exe = utils.get_python_exe()
+            python_exe = get_python_exe()
             vendor_path = os.path.join(FreeCAD.getUserAppDataDir(), "AdditionalPythonPackages")
             if not os.path.exists(vendor_path):
                 os.makedirs(vendor_path)

src/Mod/AddonManager/addonmanager_preferences_defaults.json

@@ -25,7 +25,6 @@
     "PrimaryAddonsSubmoduleURL":
         "https://raw.githubusercontent.com/FreeCAD/FreeCAD-addons/master/.gitmodules",
     "ProxyUrl": "",
-    "PythonExecutableForPip": "Not set",
     "RemoteIconCacheURL": "https://addons.freecad.org/icon_cache.zip",
     "SelectedAddon": "",
     "ShowBranchSwitcher": false,

src/Mod/AddonManager/addonmanager_utilities.py

@@ -345,40 +345,6 @@ def is_float(element: Any) -> bool:
         return False
 
 
-def get_python_exe() -> str:
-    """Find Python. In preference order
-    A) The value of the PythonExecutableForPip user preference
-    B) The executable located in the same bin directory as FreeCAD and called "python3"
-    C) The executable located in the same bin directory as FreeCAD and called "python"
-    D) The result of a shutil search for your system's "python3" executable
-    E) The result of a shutil search for your system's "python" executable"""
-    prefs = fci.ParamGet("User parameter:BaseApp/Preferences/Addons")
-    python_exe = prefs.GetString("PythonExecutableForPip", "Not set")
-    fc_dir = fci.DataPaths().home_dir
-    if not python_exe or python_exe == "Not set" or not os.path.exists(python_exe):
-        python_exe = os.path.join(fc_dir, "bin", "python3")
-        if "Windows" in platform.system():
-            python_exe += ".exe"
-
-    if not python_exe or not os.path.exists(python_exe):
-        python_exe = os.path.join(fc_dir, "bin", "python")
-        if "Windows" in platform.system():
-            python_exe += ".exe"
-
-    if not python_exe or not os.path.exists(python_exe):
-        python_exe = shutil.which("python3")
-
-    if not python_exe or not os.path.exists(python_exe):
-        python_exe = shutil.which("python")
-
-    if not python_exe or not os.path.exists(python_exe):
-        return ""
-
-    python_exe = python_exe.replace("/", os.path.sep)
-    prefs.SetString("PythonExecutableForPip", python_exe)
-    return python_exe
-
-
 def get_pip_target_directory():
     # Get the default location to install new pip packages
     major, minor, _ = platform.python_version_tuple()

src/Mod/AddonManager/manage_python_dependencies.py

@@ -36,6 +36,7 @@ from typing import Dict, List, Tuple
 
 import FreeCAD
 import FreeCADGui
+from freecad.utils import get_python_exe
 from PySide import QtCore, QtGui, QtWidgets
 
 import addonmanager_utilities as utils
@@ -89,7 +90,7 @@ def call_pip(args) -> List[str]:
     """Tries to locate the appropriate Python executable and run pip with version checking
     disabled. Fails if Python can't be found or if pip is not installed."""
 
-    python_exe = utils.get_python_exe()
+    python_exe = get_python_exe()
     pip_failed = False
     if python_exe:
         call_args = [python_exe, "-m", "pip", "--disable-pip-version-check"]