update doc (#397)

Author: Nicole00

docs/1_started.md

@@ -10,7 +10,7 @@ pip install nebula5_python==5.2.0
 from source
 
 ```bash
-git clone -b https://github.com/vesoft-inc/nebula-python.git
+git clone -b dev https://github.com/vesoft-inc/nebula-python.git
 cd nebula-python
 pip install -e .
 ```
@@ -127,6 +127,23 @@ with NebulaClient(
 
 If you prefer manual lifecycle control, you can explicitly open and close clients.
 
+- Sync version:
+
+```python
+from nebulagraph_python import NebulaClient
+
+client = NebulaClient(
+    hosts=["127.0.0.1:9669"],
+    username="root",
+    password="NebulaGraph01",
+)
+try:
+    result = client.execute("RETURN 1 AS a, 2 AS b")
+    result.print()
+finally:
+    client.close()
+```
+
 - Async version:
 
 ```python