尝试使用for循环在表中生成每个月

I have created a table in panda/python to create a table with month as a column and the months/year will be displayed in that column. I've been trying to make it so it shows month after month, so lets say jan and then feb. But the issue I'm facing is that it keeps showing the same month and year throughout the entire column as you can see the month march has been appearing throughout the entire column.I have created a table in panda/python to creat