BOM to Part List

Hi everyone,

So I am new to the forum but been following it for a few years now.
So I've been having trouble finding a solution for this problem on this forum, though I am pretty sure there is one.
I have this Bill Of Materials(BOM), which consists of 4 columns - Level(1..9), Part Number, Description and Quantity.
I need to convert the BOM to a part list so each part in the BOM will appear once, and the Quantity shown for it will be the sum of all of it appearances throughout the BOM, including of course multiplying it by it's parent's qty and so on.
I attached a file with an example with it, though the real BOM I need to convert is about a 1000 lines long and with levels up to 20.

Thank you very much!