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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 reset_frequencies(self, frequency=0):
 """Resets all stored frequencies for the cache :keyword int frequency: Frequency to reset to, must be >= 0"""


        frequency = max(frequency, 0)

        for key in self._store.keys():
            self._store[key] = (self._store[key][0], frequency)

        return frequency