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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def follow_link(self, link=None, *args, **kwargs):
 """Follow a link. If ``link`` is a bs4.element.Tag (i.e. from a previous call to :func:`links` or :func:`find_link`), then follow the link. If ``link`` doesn't have a *href*-attribute or is None, treat ``link`` as a url_regex and look it up with :func:`find_link`. Any additional arguments specified are forwarded to this function. If the link is not found, raise :class:`LinkNotFoundError`. Before raising, if debug is activated, list available links in the page and launch a browser. :return: Forwarded from :func:`open_relative`. """

        link = self._find_link_internal(link, args, kwargs)

        referer = self.get_url()
        headers = {'Referer': referer} if referer else None

        return self.open_relative(link['href'], headers=headers)