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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 convert_to_sconsign(self):
 """ Converts this FileBuildInfo object for writing to a .sconsign file This replaces each Node in our various dependency lists with its usual string representation: relative to the top-level SConstruct directory, or an absolute path if it's outside. """

        if os_sep_is_slash:
            node_to_str = str
        else:
            def node_to_str(n):
                try:
                    s = n.get_internal_path()
                except AttributeError:
                    s = str(n)
                else:
                    s = s.replace(OS_SEP, '/')
                return s
        for attr in ['bsources', 'bdepends', 'bimplicit']:
            try:
                val = getattr(self, attr)
            except AttributeError:
                pass
            else:
                setattr(self, attr, list(map(node_to_str, val)))