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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 md5(self):
 """ Get an MD5 reflecting everything in the DataStore. Returns md5: str, MD5 in hexadecimal """

        hasher = hashlib.md5()
        for key in sorted(self.data.keys()):
            hasher.update(self.data[key].md5().encode('utf-8'))
        md5 = hasher.hexdigest()
        return md5