Add Python grid demo (insertion sort)

Author: Susannah Klaneček

demos/python/insertion_sort.py

@@ -0,0 +1,39 @@
+"""Python demo for sorting using VS Code Debug Visualizer."""
+import json
+
+
+def serialize(arr):
+    """Serialize an array into a format the visualizer can understand."""
+    formatted = {
+        "kind": {"grid": True},
+        "rows": [
+            {
+                "columns": [
+                    {"content": str(value), "tag": str(value)} for value in arr
+                ],
+            }
+        ],
+    }
+    return json.dumps(formatted)
+
+
+arr = [6, 9, 3, 12, 1, 11, 5, 13, 8, 14, 2, 4, 10, 0, 7]
+
+# Put serialized into the Debug Visualizer console
+serialized = serialize(arr)
+
+# Set a breakpoint on the line below and go through the code in debug mode to
+# watch it update
+for target_idx in range(1, len(arr)):
+    target_value = arr[target_idx]
+    compare_idx = target_idx - 1
+
+    while compare_idx >= 0 and arr[compare_idx] > target_value:
+        arr[compare_idx + 1] = arr[compare_idx]
+        serialized = serialize(arr)
+        compare_idx -= 1
+
+    arr[compare_idx + 1] = target_value
+    serialized = serialize(arr)
+
+assert arr == sorted(arr)