Add spartan-graphql Python client library

src/code/language-support/python/client/spartan-graphql.md

@@ -0,0 +1,96 @@
+---
+name: Spartan GraphQL
+description: Compile GraphQL documents into a typed Python package with no imposed transport, no runtime dependencies, and no redundant validation.
+github: tibdex/spartan-graphql
+tags:
+  - tools-and-libraries
+  - frontend
+---
+
+> **Spartan**, _adj._ … distinguished by simplicity, frugality, courage, or brevity of speech.
+>
+> — _Oxford English Dictionary_
+
+Spartan GraphQL compiles GraphQL documents into a typed Python package, and stops there:
+
+- **no imposed transport**: bytes in, bytes out;
+- **no runtime dependencies**: nothing to install or upgrade (apart from `typing-extensions` before Python 3.15);
+- **no redundant validation**: just dicts, statically checked (by mypy, Pyright, Pyrefly, ty, etc.).
+
+Install spartan-graphql:
+
+```bash
+pip install spartan-graphql
+```
+
+Write your operations in a `bookshop/get_order.graphql` file:
+
+```graphql
+query GetOrder($id: ID!) {
+  order(id: $id) {
+    id
+    status
+  }
+}
+```
+
+Point a `bookshop/graphql.config.yml` file at your schema and documents:
+
+```yaml
+schema: schema.graphqls
+documents: "*.graphql"
+extensions:
+  spartan:
+    moduleRoot: ..
+    package: bookshop.graphql
+```
+
+Generate the package:
+
+```bash
+spartan-graphql bookshop/graphql.config.yml
+```
+
+Bring your own transport, here in `bookshop/transport.py` and with the standard library alone:
+
+```python
+from typing import Literal
+from urllib.request import Request as HTTPRequest, urlopen
+
+from bookshop.graphql.runtime import Request
+
+
+def send[Data](request: Request[Literal["query", "mutation"], Data], /) -> Data:
+    prepared = request.prepare()
+    http_request = HTTPRequest(
+        "https://bookshop.example/graphql",
+        data=bytes(prepared),
+        headers={
+            "Accept": "application/graphql-response+json",
+            "Content-Type": "application/json",
+        },
+    )
+
+    with urlopen(http_request) as response:
+        return prepared.parse(response.read())
+```
+
+And let your type checker verify every variable and every field of the response:
+
+```python
+from typing import Literal, assert_type
+
+from bookshop.get_order_graphql import GetOrder
+from bookshop.transport import send
+
+data = send(GetOrder({"id": "o1"}))
+order = data["order"]
+
+# `Query.order` is nullable, so the type checker requires this check.
+if order is None:
+    print("No such order.")
+else:
+    assert_type(order["id"], str)
+    assert_type(order["status"], Literal["PENDING", "SHIPPED", "DELIVERED", "CANCELED"])
+    print(f"Order {order['id']} is {order['status']}.")
+```