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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 is_alive(self):
 """ Test Function to check WHAT IF servers are up and running. """

        
        u = urllib.urlopen("http://wiws.cmbi.ru.nl/rest/TestEmpty/id/1crn/")
        x = xml.dom.minidom.parse(u)
        self.alive = len(x.getElementsByTagName("TestEmptyResponse"))

        return self.alive