leetcode.com/python/1153_String_Transforms_Into_Another_String.py

# Source: https://tinyurl.com/tvppgc4

class Solution(object):
    def canConvert(self, str1, str2):
        """
        :type str1: str
        :type str2: str
        :rtype: bool
        """
        if str1 == str2:
            return True
        m = {}
        for i in range(len(str1)):
            if str1[i] not in m:
                m[str1[i]] = str2[i]
            elif m[str1[i]] != str2[i]:
                return False
        return len(set(str2)) < 26