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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):
 """ Return an MD5 hash of the current array. Returns md5: str, hexadecimal MD5 of the array """

        if self._modified_m or not hasattr(self, '_hashed_md5'):
            if self.flags['C_CONTIGUOUS']:
                hasher = hashlib.md5(self)
                self._hashed_md5 = hasher.hexdigest()
            else:
                # the case where we have sliced our nice
                # contiguous array into a non- contiguous block
                # for example (note slice *after* track operation):
                # t = util.tracked_array(np.random.random(10))[::-1]
                contiguous = np.ascontiguousarray(self)
                hasher = hashlib.md5(contiguous)
                self._hashed_md5 = hasher.hexdigest()
        self._modified_m = False
        return self._hashed_md5