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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 url(self, key, includeToken=None):
 """ Build a URL string with proper token argument. Token will be appended to the URL if either includeToken is True or CONFIG.log.show_secrets is 'true'. """

        if self._token and (includeToken or self._showSecrets):
            delim = '&' if '?' in key else '?'
            return '%s%s%sX-Plex-Token=%s' % (self._baseurl, key, delim, self._token)
        return '%s%s' % (self._baseurl, key)