Added UpdateBHoMPackages method to update missing/old python packages.

Python_Engine/Compute/BasePythonEnvironment.cs

@@ -60,7 +60,11 @@ public static PythonEnvironment BasePythonEnvironment(
             bool exists = File.Exists(targetExecutable);
 
             if (exists && reload)
-                return new PythonEnvironment() { Name = Query.ToolkitName(), Executable = targetExecutable };
+            {
+                PythonEnvironment env = new PythonEnvironment() { Name = Query.ToolkitName(), Executable = targetExecutable };
+                UpdateBHoMPackages(env);
+                return env;
+            }
 
             if (exists && !reload)
                 // remove all existing environments and kernels

Python_Engine/Compute/UpdateBHoMPackages.cs

@@ -0,0 +1,110 @@
+/*
+ * This file is part of the Buildings and Habitats object Model (BHoM)
+ * Copyright (c) 2015 - 2026, the respective contributors. All rights reserved.
+ *
+ * Each contributor holds copyright over their respective contributions.
+ * The project versioning (Git) records all such contribution source information.
+ *                                           
+ *                                                                              
+ * The BHoM is free software: you can redistribute it and/or modify         
+ * it under the terms of the GNU Lesser General Public License as published by  
+ * the Free Software Foundation, either version 3.0 of the License, or          
+ * (at your option) any later version.                                          
+ *                                                                              
+ * The BHoM is distributed in the hope that it will be useful,              
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of               
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                 
+ * GNU Lesser General Public License for more details.                          
+ *                                                                            
+ * You should have received a copy of the GNU Lesser General Public License     
+ * along with this code. If not, see <https://www.gnu.org/licenses/lgpl-3.0.html>.      
+ */
+
+using BH.oM.Base;
+using BH.oM.Base.Attributes;
+using BH.oM.Python;
+using BH.oM.Python.Enums;
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Diagnostics;
+using System.IO;
+using System.Linq;
+using System.Text;
+
+namespace BH.Engine.Python
+{
+    public static partial class Compute
+    {
+        [Description("Using the environment name (and version if the environment name is the base python environment), directly install/update missing BHoM packages.")]
+        [Input("environmentName", "The name of the environment to update.")]
+        [Input("version", "If the environment name is the name of the base python environment, the version that needs updating.")]
+        public static void UpdateBHoMPackages(this string environmentName, PythonVersion version = PythonVersion.Undefined)
+        {
+            //construct the expected PythonEnvironment and pass to UpdateBHoMPackages
+            PythonEnvironment env = new PythonEnvironment()
+            {
+                Name = environmentName,
+            };
+
+            //python version is only used if the environment name is this toolkits name.
+            if (environmentName == Query.ToolkitName())
+            {
+                if (version == PythonVersion.Undefined)
+                {
+                    BH.Engine.Base.Compute.RecordError("The version must be specified when updating BHoM packages for a base python environment. No updates have occurred.");
+                    return;
+                }
+
+                env.Executable = Path.Combine(Query.DirectoryBaseEnvironment(version), "python.exe");
+            }
+            else
+                env.Executable = Query.VirtualEnvironmentExecutable(environmentName);
+
+            UpdateBHoMPackages(env);
+        }
+
+        /***************************************************/
+
+        [Description("Using a PythonEnvironment, directly install/update missing BHoM packages.")]
+        [Input("environment", "The python environment to update.")]
+        public static void UpdateBHoMPackages(this PythonEnvironment environment)
+        {
+            if (!File.Exists(environment.Executable))
+            {
+                BH.Engine.Base.Compute.RecordError($"Given environment or base install {environment.Executable} does not exist.");
+                return;
+            }
+
+            //`python -m pip list -e --format json` lists all environment packages that are editable installs.
+            //As all BHoM packages are editable installs, this handily lists all the packages that should be updated if necessary.
+            //side effect of updating other editable installs if they have changed, but I suspect this won't be a problem as anyone who has these would update packages manually instead.
+            System.Diagnostics.Process process = new System.Diagnostics.Process()
+            {
+                StartInfo = new System.Diagnostics.ProcessStartInfo()
+                {
+                    FileName = environment.Executable,
+                    Arguments = $"-m pip list -e --format json",
+                    UseShellExecute = false,
+                    RedirectStandardOutput = true,
+                }
+            };
+
+            process.StartInfo.Environment["PYTHONHOME"] = "";
+            string stdOut;
+
+            using (Process p = Process.Start(process.StartInfo))
+            {
+                stdOut = p.StandardOutput.ReadToEnd();
+                p.WaitForExit();
+            }
+
+            stdOut = stdOut.TrimEnd('\r', '\n');
+
+            IEnumerable<CustomObject> objs = Serialiser.Convert.FromJsonArray(stdOut).OfType<CustomObject>();
+
+            foreach (CustomObject obj in objs)
+                InstallPackageLocal(environment, (string)obj.CustomData["editable_project_location"]);
+        }
+    }
+}

Python_Engine/Compute/VirtualEnvironment.cs

@@ -60,7 +60,11 @@ public static PythonEnvironment VirtualEnvironment(this PythonVersion version, s
             bool exists = Query.VirtualEnvironmentExists(name);
 
             if (exists && reload)
-                return new PythonEnvironment() { Name = name, Executable = targetExecutable };
+            {
+                PythonEnvironment env = new PythonEnvironment() { Name = name, Executable = targetExecutable };
+                UpdateBHoMPackages(env);
+                return env;
+            }
 
             if (exists && !reload)
             {