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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 get_word_app ():
 """Return open Word.Application handle, or None if Word is not available on this system."""

    if not has_word():
        return None
    # Since this function is called from different threads, initialize
    # the COM layer.
    pythoncom.CoInitialize()
    import win32com.client
    app = win32com.client.gencache.EnsureDispatch("Word.Application")
    app.Visible = False
    return app