def pseudonymize(self, content):
    if not content: return content
    content_modified = ''
    start = 0
    for mo in re.finditer("\[\*\*[^\[]*\*\*\]", content):
        replacement = self.mapper.get_mapping(mo.group(0))
        content_modified += content[start: mo.start()]
        content_modified += replacement
        start = mo.end()

    if start < len(content):
        content_modified += content[start: len(content)]
    return content_modified