Fix alltoallv build and Python import errors

- Add missing accumDtype and symmetricMemory params to NativeAlgorithm
  lambda signatures in alltoallv_fullmesh.cu to match KernelFunc and
  ContextKeyGenFunc typedefs
- Use Cpp-prefixed binding names in alltoallv_single.py imports
  (CppCommunicator, CppDataType, etc.)
- Add missing symmetric_memory=False arg to algo.execute() call
- Fix test imports to use mscclpp public API instead of raw _mscclpp

python/mscclpp/ext/alltoallv_single.py

@@ -17,11 +17,11 @@ import torch
 import torch.distributed as dist
 from typing import Optional, List, Tuple
 from mscclpp._mscclpp import (
-    Communicator,
-    TcpBootstrap,
-    DataType,
-    ReduceOp,
-    CommResult,
+    CppCommunicator as Communicator,
+    CppTcpBootstrap as TcpBootstrap,
+    CppDataType as DataType,
+    CppReduceOp as ReduceOp,
+    CppCommResult as CommResult,
 )
 from mscclpp.ext.algorithm_collection_builder import AlgorithmCollectionBuilder
 
@@ -323,6 +323,7 @@ class MscclppAlltoAllV:
             None,  # executor (not needed for native algos)
             0,     # nblocks (auto)
             0,     # nthreads_per_block (auto)
+            False, # symmetric_memory
             self._extras,
         )
 

python/test/test_alltoallv_mscclpp.py

@@ -130,11 +130,11 @@ def main():
         print("=" * 60)
 
     # Import after torch.distributed init
-    from mscclpp._mscclpp import (
+    from mscclpp import (
         Communicator,
         TcpBootstrap,
-        UniqueId,
     )
+    from mscclpp._mscclpp import CppUniqueId as UniqueId
     from mscclpp.ext.alltoallv_single import MscclppAlltoAllV
     
     # Create mscclpp communicator with TcpBootstrap