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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 _genpath(self, filename, mhash):
 """Generate the path to a file in the cache. Does not check to see if the file exists. Just constructs the path where it should be. """

        mhash = mhash.hexdigest()
        return os.path.join(self.mh_cachedir, mhash[0:2], mhash[2:4],
                            mhash, filename)