Basic markdown file splitter in Python

#!/usr/bin/env python3

import re
import unicodedata

def main():
    """
    Splits text files at specified points determined with regex and saves the splitted chunks
    of data as separate files. Names of the new files are determined by the line at
    which the split occurs.
    """

    """Configuration:"""
    source_file = "kissatkoiria.md"
    split_regex = "^# "
    encoding = "utf8"
    extension = ".md"

    p_obj = re.compile(split_regex)

    with open(source_file, encoding=encoding) as filehandle:
        chunk = ""
        splitting_line = ""
        chunk_number = 0

        for line in filehandle:
            if p_obj.search(line) is not None:
                if chunk:
                    filename = get_filename(splitting_line)
                    save_chunk(filename, chunk, chunk_number, extension)
                chunk = ""
                splitting_line = line
                chunk_number += 1
            chunk += line

        # Save the last chunk if needed
        if chunk:
            filename = get_filename(splitting_line)
            save_chunk(filename, chunk, chunk_number, extension)


def save_chunk(filename: str, chunk: str, chunk_number: int, extension: str):
    if not filename:
        filename = f"unknown_chunk_{chunk_number}"
    complete_filename = f"{filename}{extension}"

    print(f"\n\n***** Saving chunk number {chunk_number} as {complete_filename}*****")

    with open(complete_filename, "w") as filehandle:
        filehandle.write(chunk)

def get_filename(splitting_line: str) -> str:
    replaced = splitting_line.replace("# ", "") # Remove the beginning markdown header syntax
    stripped = replaced.strip()
    normalized = unicodedata.normalize("NFKD", stripped)
    filename = re.sub("[./,:;]+", "", normalized)
    return filename


if __name__ == "__main__":
    main()