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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 render(self, fname=''):
 """Render the circuit expression and store the result in a file Args: fname (str):
 Path to an image file to store the result in. Returns: str: The path to the image file """

        import qnet.visualization.circuit_pyx as circuit_visualization
        from tempfile import gettempdir
        from time import time, sleep

        if not fname:

            tmp_dir = gettempdir()
            fname = os.path.join(tmp_dir, "tmp_{}.png".format(hash(time)))

        if circuit_visualization.draw_circuit(self, fname):
            done = False
            for k in range(20):
                if os.path.exists(fname):

                    done = True
                    break
                else:
                    sleep(.5)
            if done:
                return fname

        raise CannotVisualize()