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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 start_scan(self, source_id):
 """ Start a new scan of a Source. :rtype: Scan """

        target_url = self.client.get_url('SCAN', 'POST', 'create', {'source_id': source_id})
        r = self.client.request('POST', target_url, json={})
        return self.client.get_manager(Scan).create_from_result(r.json())