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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 getall(self, key, default=_marker):
 """Return a list of all values matching the key."""

        identity = self._title(key)
        res = [v for i, k, v in self._impl._items if i == identity]
        if res:
            return res
        if not res and default is not _marker:
            return default
        raise KeyError('Key not found: %r' % key)