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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 _hash_file(self, path):
 """ Compute and md5 hash for file :returns: hexadecimal md5 """


        m = hashlib.md5()
        with open(path, "rb") as f:
            while True:
                buf = f.read(128)
                if not buf:
                    break
                m.update(buf)
        return m.hexdigest()