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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 remove(self, priority, observer, callble):
 """ Remove one observer, which had priority and callble. """

        self.flush()
        for i in range(len(self) - 1, -1, -1):
            p,o,c = self[i]
            if priority==p and observer==o and callble==c:
                del self._poc[i]