pd.crosstab(data_2019.HOUR, data_2019.DAY_OF_WEEK)

DAY_OF_WEEK Friday  Monday  Saturday    Sunday  Thursday    Tuesday Wednesday
HOUR
0   204 255 256 260 225 222 192
1   121 111 198 230 116 117 145
2   128 90  217 222 84  111 96

days = ['Monday', 'Tuesday', 'Wednesday', 'Thursday',
        'Friday', 'Saturday', 'Sunday']

c = pd.crosstab(...)

c = c[days]

c = c.reindex(days, axis="columns")