outputFileName = 'single-page2'

import glob
filenames = glob.glob('*.md')
with open(outputFileName, 'w') as outfile:
    for fname in filenames:
        with open(fname) as infile:
            fileTitleString = "\n\n\n" + "# " + fname + "\n"
            outfile.write(fileTitleString)
            for line in infile:
                outfile.write(line)