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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 file_crc32(filename, chunksize=_CHUNKSIZE):
 """ calculate the CRC32 of the contents of filename """


    check = 0
    with open(filename, 'rb') as fd:
        for data in iter(lambda: fd.read(chunksize), ""):
            check = crc32(data, check)
    return check