docs: optimizate python document base on java document

docs/en/14-reference/03-connector/07-python.mdx

@@ -24,6 +24,36 @@ The source code for the Python connector is hosted on [GitHub](https://github.co
 
 We recommend using the latest version of `taospy`, regardless of the version of TDengine.
 
+## Handling Exceptions
+
+There are 4 types of exception in python connector.
+
+- The exception of Python Connector itself.
+- The exception of native library.
+- The exception of websocket
+- The exception of subscription.
+- The exception of other TDengine function modules.
+
+|Error Type|Description|Suggested Actions|
+|:--------:|:---------:|:---------------:|
+|InterfaceError|the native library is too old that it cannot support the function|please check the TDengine client version|
+|ConnectionError|connection error|please check TDengine's status and the connection params|
+|DatabaseError|database error|please upgrade Python connector to latest|
+|OperationalError|operation error||
+|ProgrammingError|||
+|StatementError|the exception of stmt||
+|ResultError|||
+|SchemalessError|the exception of stmt schemaless||
+|TmqError|the exception of stmt tmq||
+
+It usually uses try-expect to handle exceptions in python. For exception handling, please refer to [Python Errors and Exceptions Documentation](https://docs.python.org/3/tutorial/errors.html).
+
+All exceptions from the Python Connector are thrown directly. Applications should handle these exceptions. For example:
+
+```python
+{{#include docs/examples/python/handle_exception.py}}
+```
+
 ## Supported features
 
 - Native connections support all the core features of TDengine, including connection management, SQL execution, bind interface, subscriptions, and schemaless writing.
@@ -343,6 +373,8 @@ For a more detailed description of the `sql()` method, please refer to [RestClie
 </TabItem>
 <TabItem value="websocket" label="WebSocket connection">
 
+The `Connection` class contains both an implementation of the PEP249 Connection interface (e.g., the `cursor()` method and the `close()` method) and many extensions (e.g., the `execute()`, `query()`, `schemaless_insert()`, and `subscribe()` methods).
+
 ```python
 {{#include docs/examples/python/connect_websocket_examples.py:basic}}
 ```
@@ -353,6 +385,46 @@ For a more detailed description of the `sql()` method, please refer to [RestClie
 </TabItem>
 </Tabs>
 
+### Querying Data
+
+<Tabs defaultValue="rest">
+<TabItem value="native" label="native connection">
+
+The `query` method of the `TaosConnection` class can be used to query data and return the result data of type `TaosResult`.
+
+```python
+{{#include docs/examples/python/connection_usage_native_reference.py:query}}
+```
+
+:::tip
+The queried results can only be fetched once. For example, only one of `fetch_all()` and `fetch_all_into_dict()` can be used in the example above. Repeated fetches will result in an empty list.
+:::
+
+</TabItem>
+
+<TabItem value="rest" label="REST connection">
+
+The `RestClient` class is a direct wrapper for the [REST API](/reference/rest-api). It contains only a `sql()` method for executing arbitrary SQL statements and returning the result.
+
+```python
+{{#include docs/examples/python/rest_client_example.py}}
+```
+
+For a more detailed description of the `sql()` method, please refer to [RestClient](https://docs.taosdata.com/api/taospy/taosrest/restclient.html).
+
+</TabItem>
+
+<TabItem value="websocket" label="WebSocket connection">
+
+The `query` method of the `TaosConnection` class can be used to query data and return the result data of type `TaosResult`.
+
+```python
+{{#include docs/examples/python/connect_websocket_examples.py:basic}}
+```
+
+</TabItem>
+</Tabs>
+
 ### Usage with req_id
 
 By using the optional req_id parameter, you can specify a request ID that can be used for tracing.
@@ -811,14 +883,6 @@ bind multiple rows at once |
 
 ## Other notes 
 
-### Exception handling
-
-All errors from database operations are thrown directly as exceptions and the error message from the database is passed up the exception stack. The application is responsible for exception handling. For example:
-
-```python
-{{#include docs/examples/python/handle_exception.py}}
-```
-
 ### About nanoseconds
 
 Due to the current imperfection of Python's nanosecond support (see link below), the current implementation returns integers at nanosecond precision instead of the `datetime` type produced by `ms` and `us`, which application developers will need to handle on their own. And it is recommended to use pandas' to_datetime(). The Python Connector may modify the interface in the future if Python officially supports nanoseconds in full.

docs/zh/08-connector/30-python.mdx

@@ -25,6 +25,36 @@ Python 连接器的源码托管在 [GitHub](https://github.com/taosdata/taos-con
 
 无论使用什么版本的 TDengine 都建议使用最新版本的 `taospy`。
 
+## 处理异常
+
+Python 连接器可能会产生 4 种异常：
+
+- Python 连接器本身的异常
+- 原生连接方式的异常
+- websocket 连接方式异常
+- 数据订阅异常
+- TDengine 其他功能模块的异常
+
+|Error Type|Description|Suggested Actions|
+|:--------:|:---------:|:---------------:|
+|InterfaceError|taosc 版本太低，不支持所使用的接口|请检查 TDengine 客户端版本|
+|ConnectionError|数据库链接错误|请检查 TDengine 服务端状态和连接参数|
+|DatabaseError|数据库错误|请检查 TDengine 服务端版本，并将 Python 连接器升级到最新版|
+|OperationalError|操作错误|API 使用错误，请检查代码|
+|ProgrammingError|||
+|StatementError|stmt 相关异常||
+|ResultError|||
+|SchemalessError|schemaless 相关异常||
+|TmqError|tmq 相关异常||
+
+Python 中通常通过 try-expect 处理异常，异常处理相关请参考 [Python 错误和异常文档](https://docs.python.org/3/tutorial/errors.html)。
+
+Python Connector 的所有数据库操作如果出现异常，都会直接抛出来。由应用程序负责异常处理。比如：
+
+```python
+{{#include docs/examples/python/handle_exception.py}}
+```
+
 ## 支持的功能
 
 - 原生连接支持 TDengine 的所有核心功能， 包括： 连接管理、执行 SQL、参数绑定、订阅、无模式写入（schemaless）。
@@ -32,7 +62,7 @@ Python 连接器的源码托管在 [GitHub](https://github.com/taosdata/taos-con
 
 ## 安装
 
-### 准备
+### 安装前准备
 
 1. 安装 Python。新近版本 taospy 包要求 Python 3.6.2+。早期版本 taospy 包要求 Python 3.7+。taos-ws-py 包要求 Python 3.7+。如果系统上还没有 Python 可参考 [Python BeginnersGuide](https://wiki.python.org/moin/BeginnersGuide/Download) 安装。
 2. 安装 [pip](https://pypi.org/project/pip/)。大部分情况下 Python 的安装包都自带了 pip 工具， 如果没有请参考 [pip documentation](https://pip.pypa.io/en/stable/installation/) 安装。
@@ -274,7 +304,7 @@ Transfer-Encoding: chunked
 </TabItem>
 </Tabs>
 
-## 示例程序
+## 使用示例
 
 ### 基本使用
 
@@ -343,6 +373,10 @@ TaosCursor 类使用原生连接进行写入、查询操作。在客户端多线
 </TabItem>
 <TabItem value="websocket" label="WebSocket 连接">
 
+#### Connection 类的使用
+
+`Connection` 类既包含对 PEP249 Connection 接口的实现(如：cursor方法和 close 方法)，也包含很多扩展功能（如： execute、 query、schemaless_insert 和 subscribe 方法。
+
 ```python
 {{#include docs/examples/python/connect_websocket_examples.py:basic}}
 ```
@@ -353,6 +387,46 @@ TaosCursor 类使用原生连接进行写入、查询操作。在客户端多线
 </TabItem>
 </Tabs>
 
+### 查询数据
+
+<Tabs defaultValue="rest">
+<TabItem value="native" label="原生连接">
+
+`TaosConnection` 类的 `query` 方法可以用来查询数据，返回 `TaosResult` 类型的结果数据。
+
+```python
+{{#include docs/examples/python/connection_usage_native_reference.py:query}}
+```
+
+:::tip
+查询结果只能获取一次。比如上面的示例中 `fetch_all()` 和 `fetch_all_into_dict()` 只能用一个。重复获取得到的结果为空列表。
+:::
+
+</TabItem>
+
+<TabItem value="rest" label="REST 连接">
+
+RestClient 类是对于 REST API 的直接封装。它只包含一个 sql() 方法用于执行任意 SQL 语句， 并返回执行结果。
+
+```python
+{{#include docs/examples/python/rest_client_example.py}}
+```
+
+对于 `sql()` 方法更详细的介绍， 请参考 [RestClient](https://docs.taosdata.com/api/taospy/taosrest/restclient.html)。
+
+</TabItem>
+
+<TabItem value="websocket" label="WebSocket 连接">
+
+`TaosConnection` 类的 `query` 方法可以用来查询数据，返回 `TaosResult` 类型的结果数据。
+
+```python
+{{#include docs/examples/python/connect_websocket_examples.py:basic}}
+```
+
+</TabItem>
+</Tabs>
+
 ### 与 req_id 一起使用
 
 使用可选的 req_id 参数，指定请求 id，可以用于 tracing
@@ -807,7 +881,7 @@ stmt.close()
 </TabItem>
 </Tabs>
 
-### 其它示例程序
+### 更多示例程序
 
 | 示例程序链接                                                                                                  | 示例程序内容            |
 | ------------------------------------------------------------------------------------------------------------- | ----------------------- |
@@ -819,14 +893,6 @@ stmt.close()
 
 ## 其它说明 
 
-### 异常处理
-
-所有数据库操作如果出现异常，都会直接抛出来。由应用程序负责异常处理。比如：
-
-```python
-{{#include docs/examples/python/handle_exception.py}}
-```
-``
 ### 关于纳秒 (nanosecond)
 
 由于目前 Python 对 nanosecond 支持的不完善(见下面的链接)，目前的实现方式是在 nanosecond 精度时返回整数，而不是 ms 和 us 返回的 datetime 类型，应用开发者需要自行处理，建议使用 pandas 的 to_datetime()。未来如果 Python 正式完整支持了纳秒，Python 连接器可能会修改相关接口。