Can someone please breakdown the for loop number patterns (tree shapes)?

Question

After going through basic python and exposure to pandas and numpy, I decided to learn by doing for the next few days. In the process I understood function and for loops but the tree shape pattern just defeats me. The code is found below:

print("Fouth number pattern")
lastNumber = 9

for row in range(1, lastNumber):
for column in range(-1 + row, - 1, - 1):
print(format(format(2**column, "4d"), end=" ")
print(" ")

Answer 1

This Code will Print 8 rows (lastNumber - 1).
Each row will have x collumns. The First has 1, the second 2 etc... (Row - 1, until -1, in descending Order) .
The columns will then contain 2 to the Power of column number.. (128, 64, 32, ... , 1)
At the end of each column, a space will be ran printed (end = ' '), and the Numbers will have 4 Digits ("4d")
At the end of each row, there will be a new line...

Regarding Format, See Code below:

lastNum = 9

for row in range(1, lastNum):
for col in range(-1+row, -1, -1):
print("{:4d}".format(2**col), end=' ')
print(" ")