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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 isRunning(self, waitTime=0):
 """ If PID isn't set yet, checks if there is a window with the specified title. """

        waitUntil = time.time() + waitTime
        while True:
            if self.getPID() > 0:
                return True
            else:
                self._pid = PlatformManager.getWindowPID(PlatformManager.getWindowByTitle(re.escape(self._title)))

            # Check if we've waited long enough
            if time.time() > waitUntil:
                break
            else:
                time.sleep(self._defaultScanRate)
        return self.getPID() > 0