def reverse_long_words(sentence: str) -> str:
 """
 Reverse all words that are longer than 4 characters in a sentence.

 >>> reverse_long_words("Hey wollef sroirraw")
 'Hey fellow warriors'
 >>> reverse_long_words("nohtyP is nohtyP")
 'Python is Python'
 >>> reverse_long_words("1 12 123 1234 54321 654321")
 '1 12 123 1234 12345 123456'
 """
 return " ".join(
 "".join(word[::-1]) if len(word) > 4 else word for word in sentence.split()
 )


if __name__ == "__main__":
 import doctest

 doctest.testmod()
 print(reverse_long_words("Hey wollef sroirraw"))