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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(self, key):
 """ Get the full path for the given cache key. :param key: The cache key :type key: str :rtype: str """

        hash_type, parts_count = self._HASHES[self._hash_type]
        h = hash_type(encode(key)).hexdigest()

        parts = [h[i:i+2] for i in range(0, len(h), 2)][:parts_count]

        return os.path.join(self._directory, os.path.sep.join(parts), h)