Remove repeated dates after "--" strings in Markdown filenames

clean_repeated_dates_in_filenames.py

import os

def find_second(string, substring):
   return string.find(substring, string.find(substring) + 1)

for root, dirs, files in os.walk("."):
    for file in files:
        if file.endswith(".md"):
            old_path = os.path.join(root, file)
            second_location = find_second(file, "--")
            if second_location != -1:
                file = file[:second_location-1] + ".md"
                new_path = os.path.join(root, file)
                os.rename(old_path, new_path)
                print(new_path)
            else:
                print(old_path)