docs: def is_python_script(filename):
      '''Checks a file to see if it's a python script of some sort.
      '''
      if filename.lower().endswith('.py'):
          return True
  
      if not os.path.isfile(filename):
          return False
  
      try:
          with open(filename, 'rb') as fp:
              if fp.read(2) != b'#!':
                  return False
              return re.match(r'.*python', str_(fp.readline()))
      except IOError:
          pass
  
      return False