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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 gets(self, addr, length):
 """Get string of bytes from given address. If any entries are blank from addr through addr+length, a NotEnoughDataError exception will be raised. Padding is not used. """

        a = array('B', asbytes('\0'*length))
        try:
            for i in range_g(length):
                a[i] = self._buf[addr+i]
        except KeyError:
            raise NotEnoughDataError(address=addr, length=length)
        return array_tobytes(a)