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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 _untrack_tendril(self, tendril):
 """ Removes the tendril from the set of tracked tendrils. """


        try:
            del self.tendrils[tendril._tendril_key]
        except KeyError:
            pass

        # Also remove from _tendrils
        try:
            del self._tendrils[tendril.proto][tendril._tendril_key]
        except KeyError:
            pass