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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 _init(self, width, len_):
 """Initializes internal data representation of the BinArray to all-0. The internal data representation is simply tightly-packed bits of all words, starting from LSB, split into bytes and stored in a bytearray. The unused trailing padding bits in the last byte must always be set to 0. """

        self._width = width
        self._len = len_
        bits = len_ * width
        self._data = bytearray(BinInt(bits).ceildiv(8))