Looks ugly:

```
df_cut = df_new[
             (
             (df_new['l_ext']==31) |
             (df_new['l_ext']==22) |
             (df_new['l_ext']==30) |
             (df_new['l_ext']==25) |
             (df_new['l_ext']==64)
             )
            ]

```

Does not work:

```
df_cut = df_new[(df_new['l_ext'] in [31, 22, 30, 25, 64])]

```

Is there an elegant and working solution of the above "problem"?