I have a data frame with 1 column, how do I remove a character from the last value in the column, for example:

```
'1234',
'4567',
'45SD',
'65SD',
'7Q98',
'Q8E7',

```

The last value is 'Q8E7', and I want to remove "," so result would be:

```
'1234',
'4567',
'45SD',
'65SD',
'7Q98',
'Q8E7'

```

(note the missing `,` after `'Q8E7'`)

This is something I need to do on a daily basis, and the number of records in the column will never be the same.

Thanks.