import os

# Walk through all directories and subdirectories from the current directory
for dirpath, dirnames, filenames in os.walk('.'):
    # For each file in the directories
    for filename in filenames:
        # If the file is a .sy file
        if filename.endswith('.sy'):
            filepath = os.path.join(dirpath, filename)
            with open(filepath, 'r+') as file:
                content = file.read()
                # Add '#include "sylib.h"' at the beginning of the file
                file.seek(0, 0)
                file.write('#include "sylib.h"\n' + content)