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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 _path_to_keys(cls, path):
 """Return a list of keys for a given path"""


        # Paths are cached for performance
        keys = _BaseFrame._path_to_keys_cache.get(path)
        if keys is None:
            keys = _BaseFrame._path_to_keys_cache[path] = path.split('.')

        return keys