Python 替換空格

請實現一個函數，將一個字符串中的每個空格替換成"20%"。例如，當字符串爲We Are Happy. 則經過替換之後的字符串爲We20%Are20%Happy.

class Solution:
    def replaceSpace(self, s):
        strLen = len(s)
        aaa = []
        for i in range(0, strLen):
            if s[i] == " ":
                aaa.append("20%")
            else:
                aaa.append(s[i])
        return ''.join(aaa)


if __name__ == '__main__':
    s = Solution()
    print(s.replaceSpace("We Are Happy "))

運行結果爲：

We20%Are20%Happy20%