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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 crc32File(filename, skip=0):
 """Computes the CRC-32 of the contents of filename, optionally skipping a certain number of bytes at the beginning of the file. """

    with open(filename, 'rb') as stream:
        discard = stream.read(skip)
        return zlib.crc32(stream.read()) & 0xffffffff