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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_guts_toc_mtime(attr, old, toc, last_build, pyc=0):
 """ rebuild is required if mtimes of files listed in old toc are newer than ast_build if pyc=1, check for .py files, too """

    for (nm, fnm, typ) in old:
        if mtime(fnm) > last_build:
            logger.info("building because %s changed", fnm)
            return True
        elif pyc and mtime(fnm[:-1]) > last_build:
            logger.info("building because %s changed", fnm[:-1])
            return True
    return False