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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 run_dot(self, args, name, parts=0, urls={}, graph_options={}, node_options={}, edge_options={}):
 """ Run graphviz 'dot' over this graph, returning whatever 'dot' writes to stdout. *args* will be passed along as commandline arguments. *name* is the name of the graph *urls* is a dictionary mapping class names to http urls Raises DotException for any of the many os and installation-related errors that may occur. """

        try:
            dot = subprocess.Popen(['dot'] + list(args),
                                   stdin=subprocess.PIPE, stdout=subprocess.PIPE,
                                   close_fds=True)
        except OSError:
            raise DotException("Could not execute 'dot'.  Are you sure you have 'graphviz' installed?")
        except ValueError:
            raise DotException("'dot' called with invalid arguments")
        except:
            raise DotException("Unexpected error calling 'dot'")

        self.generate_dot(dot.stdin, name, parts, urls, graph_options,
                          node_options, edge_options)
        dot.stdin.close()
        result = dot.stdout.read()
        returncode = dot.wait()
        if returncode != 0:
            raise DotException("'dot' returned the errorcode %d" % returncode)
        return result