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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 check_crc(f, inf, desc):
 """Compare result crc to expected value. """

    exp = inf._md_expect
    if exp is None:
        return
    ucrc = f._md_context.digest()
    if ucrc != exp:
        print('crc error - %s - exp=%r got=%r' % (desc, exp, ucrc))