Create a report using excel

[Barrowman]

How did you create the sheet? Show us your code.
I'm guessing you didn't open the file correctly.

If you do

fo= open("sheet", 'w')

it overwrites

but if you do

fo = open("sheet", 'a')

it appends to the end.

If you do

fo = open("sheet", 'a+')

it appends but if the file does not exist it will create it