What are these python lines for? What are tey doing?

[deanhystad]

I noticed that there is more space inside the bracket in in line 15 than in line 16. Why is that?

You are mistaken. Spacing is the same in both lines.

X = data.iloc[:, :8].values
Y = data.iloc[:, 8].values.reshape(-1,1)
#               ^ one space

Did you look at my example? I demonstrated the difference between lines 15 and 16 here:

evaluate("First three columns", "df.iloc[:, :3]")   # Does the same thing as line 15
evaluate("Column 2 (third column)", "df.iloc[:, 2]")  # Does the same thing as line 16