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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 cmd_exec(self, cmd):
 """ Execute commands in automate namespace """


        if not cmd:
            return
        ns = self.cmd_namespace
        import copy
        rval = True
        nscopy = copy.copy(ns)
        try:
            r = eval(cmd, ns)
            if isinstance(r, SystemObject) and not r.system:
                r.setup_system(self)
            if callable(r):
                r = r()
                cmd += "()"
            self.logger.info("Eval: %s", cmd)
            self.logger.info("Result: %s", r)
        except SyntaxError:
            r = {}
            try:
                exec (cmd, ns)
                self.logger.info("Exec: %s", cmd)
            except ExitException:
                raise
            except Exception as e:
                self.logger.info("Failed to exec cmd %s: %s.", cmd, e)
                rval = False
            for key, value in list(ns.items()):
                if key not in nscopy or not value is nscopy[key]:
                    if key in self.namespace:
                        del self.namespace[key]
                    self.namespace[key] = value
                    r[key] = value
            self.logger.info("Set items in namespace: %s", r)
        except ExitException:
            raise
        except Exception as e:
            self.logger.info("Failed to eval cmd %s: %s", cmd, e)
            return False

        return rval