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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 setDocuments(self, documenting_pid, documented_pid):
 """Add a CiTO, the Citation Typing Ontology, triple asserting that ``documenting_pid`` documents ``documented_pid``. Adds assertion: ``documenting_pid cito:documents documented_pid`` Args: documenting_pid: str PID of a Science Object that documents ``documented_pid``. documented_pid: str PID of a Science Object that is documented by ``documenting_pid``. """

        self._check_initialized()
        documenting_id = self.getObjectByPid(documenting_pid)
        documented_id = self.getObjectByPid(documented_pid)
        self.add((documenting_id, CITO.documents, documented_id))