get error for 02-chunkers-async when run from .py file raise NotImplementedError("Subclasses must implement this method")

[Sandy4321]

get error for 02-chunkers-async when run from .py file
https://github.com/aurelio-labs/semantic-chunkers/blob/main/docs/02-chunkers-async.ipynb
when run from .py file

site-packages\semantic_router\encoders\base.py", line 22, in acall
raise NotImplementedError("Subclasses must implement this method")

builtins.NotImplementedError: Subclasses must implement this method

chunker = StatisticalChunker(encoder=encoder, max_split_tokens=300)
import asyncio # Required for running async code

async def process_chunks(content):
# Call the chunker asynchronously
chunks_async = await chunker.acall(docs=[content])
return chunks_async

chunks = asyncio.run(process_chunks(content))
q = 0

[Sandy4321]

I use
from semantic_router.encoders import HuggingFaceEncoder
encoder = HuggingFaceEncoder()