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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 read_md5(self, hex=False):
 """ Calculate the md5 hash for this file. hex - Return the digest as hex string. This reads through the entire file. """

        f = self.open('rb')
        try:
            m = hashlib.md5()
            while True:
                d = f.read(8192)
                if not d:
                    break
                m.update(d)
        finally:
            f.close()
        if hex:
            return m.hexdigest()
        else:
            return m.digest()