这是我的文本文件：
0019121002313002316003135
0057936000814000814003023
0081638001519001523001176
0090531001841001842002633
0111210001515001518000912
0115400001807001828001593
我希望处理后的输出为：
0019121,002313,002316,003135
0057936,000814,000814,003023
0081638,001519,001523,001176
0090531,001841,001842,002633
0111210,001515,001518,000912
0115400,001807,001828,001593
我该怎么做呢？