def __repr__(self):
        return "<NamedRequirements({}{})>".format(
            self.name,
            ", filename='{}'".format(self.filename.name) if self.filename
            else "")
def finalize_options(self):
    self.set_undefined_options('install',
                               ('install_headers', 'install_dir'),
                               ('force', 'force'))