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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_cache_key(self):
 """ The cache key is a string of concatenated sorted names and values. """


        keys = list(self.params.keys())
        keys.sort()

        cache_key = str()

        for key in keys:
            if key != "api_sig" and key != "api_key" and key != "sk":
                cache_key += key + self.params[key]

        return hashlib.sha1(cache_key.encode("utf-8")).hexdigest()