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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 _int_to_words(self, pattern):
 """ Given a bit-pattern expressed an integer number, return a sequence of the individual words that make up the pattern. The number of bits per word will be obtained from the internal SPI interface. """

        try:
            bits_required = int(ceil(log(pattern, 2))) + 1
        except ValueError:
            # pattern == 0 (technically speaking, no bits are required to
            # transmit the value zero ;)
            bits_required = 1
        shifts = range(0, bits_required, self._spi.bits_per_word)[::-1]
        mask = 2 ** self._spi.bits_per_word - 1
        return [(pattern >> shift) & mask for shift in shifts]