Update SDK->sdk, and add create_dataset (#1047)

### What problem does this PR solve?

Add create_dataset method, test for it, and update SDK->sdk.

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

Signed-off-by: cecilia-uu <konghui1996@163.com>

sdk/python/ragflow/__init__.py

@@ -0,0 +1,3 @@
+import importlib.metadata
+
+__version__ = importlib.metadata.version("ragflow")

sdk/python/ragflow/ragflow.py

@@ -0,0 +1,27 @@
+#
+#  Copyright 2024 The InfiniFlow Authors. All Rights Reserved.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+#
+import os
+from abc import ABC
+
+
+class RAGFLow(ABC):
+    def __init__(self, user_key, base_url):
+        self.user_key = user_key
+        self.base_url = base_url
+
+    def create_dataset(self, name):
+        return name
+