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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 add(self, priority, observer, callble):
 """ Add an observer with priority and callble """

        #if observer is not None:
        ins = 0
        for pr, _, _ in self:
            if priority > pr:
                break
            ins += 1
        self._poc.insert(ins, (priority, weakref.ref(observer), callble))