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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 _make_key(self):
 """Make a key for caching files in the LRU cache."""

        value = (self._opener,
                 self._args,
                 'a' if self._mode == 'w' else self._mode,
                 tuple(sorted(self._kwargs.items())))
        return _HashedSequence(value)