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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 load_data(self, pdbid):
 """Loads and parses an XML resource and saves it as a tree if successful"""

        f = urlopen("http://projects.biotec.tu-dresden.de/plip-rest/pdb/%s?format=xml" % pdbid.lower())
        self.doc = etree.parse(f)