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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 get(self, key, _else=None):
 """The method to get an assets value """

        with self._lock:
            self.expired()
            # see if everything expired
            try:
                value = self._dict[key].get()
                return value
            except KeyError:
                return _else
            except ValueError:
                return _else