update readme

Signed-off-by: junjie.jiang <junjie.jiang@zilliz.com>

README.md

@@ -1,2 +1,56 @@
-# milvus-client
+# ANN Insert Operator: MilvusClient
 
+
+<br />
+
+
+
+## Desription
+
+Insert data into Milvus collections. **Please make sure you have [created Milvus Collection](https://milvus.io/docs/v2.0.x/create_collection.md) before loading the data.**
+
+<br />
+
+
+
+## Code Example
+
+### Example
+
+
+```python
+import towhee
+
+from towhee.dc2 import ops
+
+p = (
+        towhee.pipe.inputs('vec')
+        .map('vec', (), ops.ann_insert.milvus_client(host='127.0.0.1', port='19530', collection_name='test_collection'))
+        .output()
+        )
+
+p(vec)
+```
+
+### Load Collection
+
+> Please load the Collection after inserted data.
+
+```python
+collection.load()
+```
+
+<br />
+
+
+
+## Factory Constructor
+
+Create the operator via the following factory method:
+
+***ann_insert.milvus_client(collection)***
+
+<br />
+
+
+**Returns:** *None*