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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 to_filelink(self):
 """ Checks is the status of the conversion is complete and, if so, converts to a Filelink *returns* [Filestack.Filelink] ```python filelink = av_convert.to_filelink() ``` """

        if self.status != 'completed':
            return 'Audio/video conversion not complete!'

        response = utils.make_call(self.url, 'get')

        if response.ok:
            response = response.json()
            handle = re.match(
                r'(?:https:\/\/cdn\.filestackcontent\.com\/)(\w+)',
                response['data']['url']
            ).group(1)
            return filestack.models.Filelink(handle, apikey=self.apikey, security=self.security)

        raise Exception(response.text)