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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 build_byte_align_buff(bits):
 """Pad the left side of a bitarray with 0s to align its length with byte boundaries. Args: bits: A bitarray to be padded and aligned. Returns: A newly aligned bitarray. """

    bitmod = len(bits)%8
    if bitmod == 0:
        rdiff = bitarray()
    else:
        #KEEP bitarray
        rdiff = bitarray(8-bitmod)
        rdiff.setall(False)
    return rdiff+bits