如何解决TypeError:\uuuu init\uuuu（）缺少1个必需的位置参数错误

Question

我在这里检查类似的问题和答案，但我看不到代码中缺少的部分。使用此代码

class Solution:
    def __init__(self,arr):
        self.arr = arr
        
    def minDeletionSize(self):
        cnt = 0
        for n,c in enumerate(self.arr):
            sortedAsc = "".join(sorted(c))           
            sortedDesc = ''.join(reversed(sortedAsc))

            if (c != sortedAsc and c != sortedDesc):
                cnt += 1
                
        print(cnt)
    
if __name__ == '__main__':

     arrays = [["cba","daf","ghi"],["a","b"],["zyx","wvu","tsr"]]
     for arr in arrays:
         obj = Solution(arr)
         obj.minDeletionSize()

我收到了这个错误信息

TypeError: __init__() missing 1 required positional argument: 'arr'
ret = Solution().minDeletionSize(param_1)
Line 43 in _driver (Solution.py)
    _driver()
Line 54 in <module> (Solution.py)

提前谢谢