I want to extract initials from user names and next replace names with initials

```py
s = pd.DataFrame(['Robert Flitz', 'Hans Malek', 'Marek J. Beer'])

```

when i try use this function 

```py
def initials(name):
    init = ""
    for n in name.str.split():
        for i in n:
            init+=i[0]
    return init

```

it returns single string

```
initials(s[0])
'RFHMMJB'

```

I want to look it like

```
'RF'
'HM'
'MJB'

```

Any ideas?