무식하게했던것;;

morse = {
'.-':'a','-...':'b','-.-.':'c','-..':'d','.':'e','..-.':'f',
'--.':'g','....':'h','..':'i','.---':'j','-.-':'k','.-..':'l',
'--':'m','-.':'n','---':'o','.--.':'p','--.-':'q','.-.':'r',
'...':'s','-':'t','..-':'u','...-':'v','.--':'w','-..-':'x',
'-.--':'y','--..':'z'
}

	def solution(letter):
    answer = '' 
    letter = letter.split(" ")
    index =0 
    for i in letter:
        for j in range(len(letter)):
            if i in letter:
                index = letter.index(i)
                letter[index] = morse[i]
    letter = "".join(letter) 
    return letter 
    

개선

def solution(letter):
    answer = ''
    letter = letter.split(" ") 
    for i in letter: 
        answer += morse[i]
    return answer
    

한줄

def solution(letter): 
  return ''.join([morse[i] for i in letter.split(' ')])