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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 unlink(self, definition, doc1, doc2) :
        "deletes all links between doc1 and doc2"
        links = self.database[definition].fetchByExample( {"_from": doc1._id,"_to" : doc2._id}, batchSize = 100)
        for l in links :
            self.deleteEdge(l)