Add pyhccl (#503)

This is the first step to support trl vllm serve on Ascend NPU
https://github.com/vllm-project/vllm-ascend/issues/459.
This PR can work properly only when
https://github.com/vllm-project/vllm/pull/16464 is merged into vLLM.

---------

Signed-off-by: hzji210@gmail.com <hzji210@gmail.com>

tests/singlecard/test_pyhccl.py

@@ -0,0 +1,30 @@
+#
+# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
+# This file is a part of the vllm-ascend project.
+# Adapted from vllm/tests/basic_correctness/test_basic_correctness.py
+# Copyright 2023 The vLLM team.
+#
+# 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 torch
+import torch_npu  # noqa: F401
+
+from vllm_ascend.distributed.device_communicators.pyhccl_wrapper import \
+    HCCLLibrary
+
+
+def test_hcclGetUniqueId():
+    torch.npu.set_device(0)
+    lib = HCCLLibrary()
+    unique_id = lib.hcclGetUniqueId()
+    assert unique_id is not None