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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 launch(self):
 """Python API for launching TensorBoard. This method is the same as main() except it launches TensorBoard in a separate permanent thread. The configure() method must be called first. Returns: The URL of the TensorBoard web server. :rtype: str """

    # Make it easy to run TensorBoard inside other programs, e.g. Colab.
    server = self._make_server()
    thread = threading.Thread(target=server.serve_forever, name='TensorBoard')
    thread.daemon = True
    thread.start()
    return server.get_url()