Причудливый индекс Python

import numpy as np
import pandas as pd
m = np.random.randint(1,30, size = (10,3))
df = pd.DataFrame(m, columns = ["var1", "var2", "var3"])

	var1	var2	var3
0	9		9		25
1	29		9		7
2	24		27		25
3	24		29		14
4	1		1		11
5	12		12		26
6	7		24		20
7	15		8		15
8	6		19		9
9	15		28		12

df[0:2][["var1","var3"]] ## pay attention to the second square brackets
output:
  var1	var3
0	9	25
1	29	7
Tired Tarantula