config: Add codespaces config w/ Python versions

.devcontainer/Dockerfile

@@ -0,0 +1,16 @@
+FROM mcr.microsoft.com/vscode/devcontainers/base:ubuntu-20.04
+
+RUN apt-get update && apt-get install -y \
+    software-properties-common \
+    && add-apt-repository ppa:deadsnakes/ppa
+
+RUN apt-get update && apt-get install -y \
+    python3.9 python3.9-dev python3.9-venv \
+    python3.10 python3.10-dev python3.10-venv \
+    python3.11 python3.11-dev python3.11-venv \
+    python3.12 python3.12-dev python3.12-venv
+
+RUN update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.9 1 \
+    && update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.10 2 \
+    && update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.11 3 \
+    && update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.12 4

.devcontainer/devcontainer.json

@@ -0,0 +1,23 @@
+{
+    "name": "Python Dev Container",
+    "build": {
+        "dockerfile": "Dockerfile"
+    },
+    "customizations": {
+        "vscode": {
+            "settings": {
+                "python.defaultInterpreterPath": "/usr/bin/python3.12"
+            },
+            "extensions": [
+                "ms-python.python",
+                "ms-python.vscode-pylance",
+                "ms-python.debugpy",
+                "ms-azuretools.vscode-docker",
+                "mechatroner.rainbow-csv"
+            ]
+        }
+    },
+    "postCreateCommand": "python3 --version",
+    "forwardPorts": [],
+    "remoteUser": "vscode"
+}