new_contents: import glob
  import os
  from time import sleep
  import hashlib
  from subprocess import call
  
  
  def main():
      while True:
          for filename in glob.glob("*.ase"):
  
              # Try to find an existing instance for that file
              file = AseFile.find_file(filename)
  
              if file:
                  # check if md5 changed between passes
                  newFile = AseFile(filename)
                  if (newFile.hash != file.hash):
                      newFile.export()
                      AseFile.files.remove(file)
                      AseFile.files.append(newFile)
                      pass
              else:
                  # Create an instance and save it
                  file = AseFile(filename)
                  file.export()
                  AseFile.files.append(file)
  
          sleep(2)
  
  
  class AseFile:
      files = []
  
      def __init__(self, name):
          self.name = name
          self.hash = self.get_hash()
          self.png_name = os.path.splitext(self.name)[0] + ".png"
  
      def get_hash(self):
          fullpath = os.path.abspath(self.name)
          return hashlib.md5(open(fullpath, 'rb').read()).hexdigest()
  
      def export(self):
          call(["path\\to\\aseprite.exe", "--batch", self.name, "--sheet", self.png_name])
  
      @classmethod
      def find_file(cls, filename):
          for file in cls.files:
              if file.name == filename:
                  return file
              return false
  
  if __name__ == "__main__":
      main()
  
subject: Create converter.py