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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 launch_app(app_path, params=[], time_before_kill_app=15):
 """ start an app """

    import subprocess
    try:
        res = subprocess.call([app_path, params], timeout=time_before_kill_app, shell=True)
        print('res = ', res)
        if res == 0:
            return True
        else:
            return False
    except Exception as ex:
        print('error launching app  ' + str(app_path) + ' with params ' + str(params) + '\n' + str(ex))
        return False