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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 app_activate(caption):
 """ use shell to bring the application with caption to front """

    try:
        shell = win32com.client.Dispatch("WScript.Shell")
        shell.AppActivate(caption)
    except Exception as ex:
        print('error calling win32com.client.Dispatch (AppActivate)')