code: def isPythonFile(filename):
      
      if filename.endswith('.py'):
          return True
  
      # Avoid obvious Emacs backup files
      if filename.endswith("~"):
          return False
  
      max_bytes = 128
  
      try:
          with open(filename, 'rb') as f:
              text = f.read(max_bytes)
              if not text:
                  return False
      except IOError:
          return False
  
      first_line = text.splitlines()[0]
      return PYTHON_SHEBANG_REGEX.match(first_line)
docs: Return True if filename points to a Python file.