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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 start(self, timeout_secs=60):
 """Start the heroku local subprocess group and verify that it has started successfully. The subprocess output is checked for a line matching 'success_regex' to indicate success. If no match is seen after 'timeout_secs', a HerokuTimeoutError is raised. """


        def _handle_timeout(signum, frame):
            raise HerokuTimeoutError(
                "Failed to start after {} seconds.".format(timeout_secs, self._record)
            )

        if self.is_running:
            self.out.log("Local Heroku is already running.")
            return

        signal.signal(signal.SIGALRM, _handle_timeout)
        signal.alarm(timeout_secs)
        self._boot()
        try:
            success = self._verify_startup()
        finally:
            signal.alarm(0)

        if not success:
            self.stop(signal.SIGKILL)
            raise HerokuStartupError(
                "Failed to start for unknown reason: {}".format(self._record)
            )
        return True