I am kind of new to python and pandas.

I have a rather large dataset (~500.000 rows). The first column contains the date and time in the form of

```
                      created_at
0 Sun Jul 26 04:06:58 +0000 2020
1 Sun Jul 26 04:08:22 +0000 2020
2 Sun Jul 26 04:24:10 +0000 2020
3 Sun Jul 26 04:27:10 +0000 2020

```

As a first step I would like to trim that to only the month and day to get a result like this:

```
created_at
0 Jul 26
1 Jul 26
2 Jul 26
3 Jul 26

```

Ideally I would like to have it like this in the end:

```
created_at
0 07_26
1 07_26
2 07_26
3 07_26

```

Can anyone help me with some efficient methods to do that?
I would really appreciate any help!