d as a feature, otherwise, the
                name of the feature to use for adding.
        &#34;&#34;&#34;
        self.outset_name = outset_name
        self.ann_type = ann_type
        self.string_feature = string_feature

    def __call__(self, doc, **kwargs):
        txt = doc.text
        if txt is None:
            return doc
        outset = doc.annset(self.outset_name)
        for m in re.finditer(PAT_EMOJI, txt):
            infos = EMOJI2INFO.get(m.group())
            if infos is not None:
   