How to use the georinex.hatanaka.opencrx function in georinex

if isinstance(fn, io.StringIO):
        fn.seek(0)
        yield fn
    elif isinstance(fn, Path):
        finf = fn.stat()
        if finf.st_size > 100e6:
            logging.info(f'opening {finf.st_size/1e6} MByte {fn.name}')

        if fn.suffix == '.gz':
            with gzip.open(fn, 'rt') as f:
                version, is_crinex = rinex_version(first_nonblank_line(f))
                f.seek(0)

                if is_crinex and not header:
                    f = io.StringIO(opencrx(f))
                yield f
        elif fn.suffix == '.zip':
            with zipfile.ZipFile(fn, 'r') as z:
                flist = z.namelist()
                for rinexfn in flist:
                    with z.open(rinexfn, 'r') as bf:
                        f = io.StringIO(io.TextIOWrapper(bf, encoding='ascii', errors='ignore').read())
                        yield f
        elif fn.suffix == '.Z':
            if unlzw is None:
                raise ImportError('pip install unlzw3')
            with fn.open('rb') as zu:
                with io.StringIO(unlzw(zu.read()).decode('ascii')) as f:
                    yield f
        else:  # assume not compressed (or Hatanaka)
            with fn.open('r', encoding='ascii', errors='ignore') as f:

with z.open(rinexfn, 'r') as bf:
                        f = io.StringIO(io.TextIOWrapper(bf, encoding='ascii', errors='ignore').read())
                        yield f
        elif fn.suffix == '.Z':
            if unlzw is None:
                raise ImportError('pip install unlzw3')
            with fn.open('rb') as zu:
                with io.StringIO(unlzw(zu.read()).decode('ascii')) as f:
                    yield f
        else:  # assume not compressed (or Hatanaka)
            with fn.open('r', encoding='ascii', errors='ignore') as f:
                version, is_crinex = rinex_version(first_nonblank_line(f))
                f.seek(0)

                if is_crinex and not header:
                    f = io.StringIO(opencrx(f))
                yield f
    else:
        raise OSError(f'Unsure what to do with input of type: {type(fn)}')