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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 graph_easy(self):
 """Draw ascii diagram. graph-easy perl module require """

        if not os.path.isfile("/usr/bin/graph-easy"):
            print("Require 'graph-easy': Install with 'slpkg -s sbo "
                  "graph-easy'")
            self.remove_dot()
            raise SystemExit()
        subprocess.call("graph-easy {0}.dot".format(self.image), shell=True)
        self.remove_dot()
        raise SystemExit()