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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 isfortran(env, source):
 """Return 1 if any of code in source has fortran files in it, 0 otherwise."""

    try:
        fsuffixes = env['FORTRANSUFFIXES']
    except KeyError:
        # If no FORTRANSUFFIXES, no fortran tool, so there is no need to look
        # for fortran sources.
        return 0

    if not source:
        # Source might be None for unusual cases like SConf.
        return 0
    for s in source:
        if s.sources:
            ext = os.path.splitext(str(s.sources[0]))[1]
            if ext in fsuffixes:
                return 1
    return 0