Add support for including system site packages

Author: glopesdev

src/Bonsai.Scripting.Python/EnvironmentConfig.cs

@@ -13,6 +13,7 @@ public EnvironmentConfig(string pythonHome, string pythonVersion)
             Path = pythonHome;
             PythonHome = pythonHome;
             PythonVersion = pythonVersion;
+            IncludeSystemSitePackages = true;
         }
 
         public string Path { get; private set; }
@@ -21,6 +22,8 @@ public EnvironmentConfig(string pythonHome, string pythonVersion)
 
         public string PythonVersion { get; private set; }
 
+        public bool IncludeSystemSitePackages { get; private set; }
+
         public static EnvironmentConfig FromConfigFile(string configFileName)
         {
             var config = new EnvironmentConfig();
@@ -39,6 +42,10 @@ static string GetConfigValue(string line)
                 {
                     config.PythonHome = GetConfigValue(line);
                 }
+                else if (line.StartsWith("include-system-site-packages"))
+                {
+                    config.IncludeSystemSitePackages = bool.Parse(GetConfigValue(line));
+                }
                 else if (line.StartsWith("version"))
                 {
                     var pythonVersion = GetConfigValue(line);

src/Bonsai.Scripting.Python/EnvironmentHelper.cs

@@ -80,6 +80,11 @@ public static string GetPythonPath(EnvironmentConfig config)
                 }
 
                 sitePackages = Path.Combine(config.Path, "Lib", "site-packages");
+                if (config.IncludeSystemSitePackages && config.Path != config.PythonHome)
+                {
+                    var systemSitePackages = Path.Combine(config.PythonHome, "Lib", "site-packages");
+                    sitePackages = $"{sitePackages}{Path.PathSeparator}{systemSitePackages}";
+                }
             }
             else
             {
@@ -92,6 +97,13 @@ public static string GetPythonPath(EnvironmentConfig config)
                 }
 
                 sitePackages = Path.Combine(config.Path, "lib", $"python{config.PythonVersion}", "site-packages");
+                if (config.IncludeSystemSitePackages)
+                {
+                    var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+                    var localFolder = Directory.GetParent(localAppData).FullName;
+                    var systemSitePackages = Path.Combine(localFolder, "lib", $"python{config.PythonVersion}", "site-packages");
+                    sitePackages = $"{sitePackages}{Path.PathSeparator}{systemSitePackages}";
+                }
             }
 
             return $"{basePath}{Path.PathSeparator}{config.Path}{Path.PathSeparator}{sitePackages}";