code: def set_meta(target, keys, overwrite=False):
      
  
      if not os.path.exists(target):
          sys.stderr.write("The target {} does not exist.\n".format(target))
          sys.exit(1)
      if len(keys) < 2 or len(keys) % 2 > 0:
          sys.stderr.write("Need an even number of arguments.\n")
          sys.exit(1)
  
      if os.path.isdir(target):
          descfile = os.path.join(target, 'index.md')
      else:
          descfile = os.path.splitext(target)[0] + '.md'
      if os.path.exists(descfile) and not overwrite:
          sys.stderr.write("Description file '{}' already exists. "
                           "Use --overwrite to overwrite it.\n".format(descfile))
          sys.exit(2)
  
      with open(descfile, "w") as fp:
          for i in range(len(keys) // 2):
              k, v = keys[i * 2:(i + 1) * 2]
              fp.write("{}: {}\n".format(k.capitalize(), v))
      print("{} metadata key(s) written to {}".format(len(keys) // 2, descfile))
docs: Write metadata keys to .md file.
  
      TARGET can be a media file or an album directory. KEYS are key/value pairs.
  
      Ex, to set the title of test.jpg to "My test image":
  
      sigal set_meta test.jpg title "My test image"