'Add an empty ID3 tag to the file.
Args:
ID3 (ID3): An ID3 subclass to use or `None` to use the one
that used when loading.
A custom tag reader may be used in instead of the default
`ID3` object, e.g. an `mutagen.easyid3.EasyID3` reader.'

def add_tags(self, ID3=None):

    if (ID3 is None):
        ID3 = self.ID3
    if (self.tags is None):
        self.ID3 = ID3
        self.tags = ID3()
    else:
        raise error('an    ID3    tag    already    exists')
