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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 upload_chunk(self):
 """ Upload chunk of file. """

        self._retried = 0
        self._do_request()
        self.offset = int(self.request.response_headers.get('upload-offset'))
        if self.log_func:
            msg = '{} bytes uploaded ...'.format(self.offset)
            self.log_func(msg)