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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 docsfor(self, rel):  # pragma: nocover
        '''Obtains the documentation for a link relation. Opens in a webbrowser
        window'''
        prefix, _rel = rel.split(':')
        if prefix in self.curies:
            doc_url = uritemplate.expand(self.curies[prefix], {'rel': _rel})
        else:
            doc_url = rel
        print('opening', doc_url)
        webbrowser.open(doc_url)