code: def validate(self):
          
  
          with open(self.filename, "rb") as f:
              text = f.read()
  
          start_last_line = text.rfind(b"\n", 0, -1)
          if start_last_line == -1:
              return False
  
          original_text = text[:start_last_line+1]
          last_line = text[start_last_line+1:]
  
          expected_hash = hashlib.sha1(original_text).hexdigest().encode('utf8')
          match = re.search(b"[0-9a-f]{40}", last_line)
          if not match:
              return False
          actual_hash = match.group(0)
          return actual_hash == expected_hash
docs: Check if the file still has its original contents.
  
          Returns True if the file is unchanged, False if it has been tampered
          with.