Planets DataFrame select rows and columns

import sys
import pandas as pd

filename = "planets.csv"
if len(sys.argv) == 2:
    filename = sys.argv[1]

df = pd.read_csv(filename)

small = df[2:5][['Distance (AU)', 'Planet name']]
print(type(small))
print(small)
print()

other = df.iloc[3:6][['Distance (AU)', 'Planet name']]
print(type(other))
print(other)
print()

<class 'pandas.core.frame.DataFrame'>
   Distance (AU) Planet name
2           1.00       Earth
3           1.50        Mars
4           2.77       Ceres

<class 'pandas.core.frame.DataFrame'>
   Distance (AU) Planet name
3           1.50        Mars
4           2.77       Ceres
5           5.20     Jupiter