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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 view(self, filename=None, directory=None, cleanup=False):
 """Save the source to file, open the rendered result in a viewer. Args: filename: Filename for saving the source (defaults to ``name`` + ``'.gv'``) directory: (Sub)directory for source saving and rendering. cleanup (bool):
 Delete the source file after rendering. Returns: The (possibly relative) path of the rendered file. Raises: graphviz.ExecutableNotFound: If the Graphviz executable is not found. subprocess.CalledProcessError: If the exit status is non-zero. RuntimeError: If opening the viewer is not supported. Short-cut method for calling :meth:`.render` with ``view=True``. """

        return self.render(filename=filename, directory=directory, view=True,
                           cleanup=cleanup)