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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 ComputeFortranSuffixes(suffixes, ppsuffixes):
 """suffixes are fortran source files, and ppsuffixes the ones to be pre-processed. Both should be sequences, not strings."""

    assert len(suffixes) > 0
    s = suffixes[0]
    sup = s.upper()
    upper_suffixes = [_.upper() for _ in suffixes]
    if SCons.Util.case_sensitive_suffixes(s, sup):
        ppsuffixes.extend(upper_suffixes)
    else:
        suffixes.extend(upper_suffixes)