How to use the xmlschema.compat.urlunsplit function in xmlschema

base_url = add_trailing_slash(base_url_parts)
        if base_url_parts.scheme not in uses_relative:
            base_url_parts = urlsplit('file:///{}'.format(base_url))
        else:
            base_url_parts = urlsplit(base_url)

        if base_url_parts.scheme not in ('', 'file'):
            url = urljoin(base_url, url)
        else:
            url_parts = urlsplit(url)
            if url_parts.scheme not in ('', 'file'):
                url = urljoin(base_url, url)
            elif not url_parts.netloc or base_url_parts.netloc == url_parts.netloc:
                # Join paths only if host parts (netloc) are equal, using the os.path.join
                # instead of urljoin for path normalization.
                url = urlunsplit((
                    '',
                    base_url_parts.netloc,
                    os.path.normpath(os.path.join(base_url_parts.path, url_parts.path)),
                    url_parts.query,
                    url_parts.fragment,
                ))

                # Add 'file' scheme if '//' prefix is added
                if base_url_parts.netloc and not url.startswith(base_url_parts.netloc) and url.startswith('//'):
                    url = 'file:' + url

    url_parts = urlsplit(url, scheme='file')
    if url_parts.scheme not in uses_relative:
        normalized_url = 'file:///{}'.format(url_parts.geturl())  # Eg. k:/Python/lib/....
    elif url_parts.scheme != 'file':
        normalized_url = urlunsplit((

'',
                    base_url_parts.netloc,
                    os.path.normpath(os.path.join(base_url_parts.path, url_parts.path)),
                    url_parts.query,
                    url_parts.fragment,
                ))

                # Add 'file' scheme if '//' prefix is added
                if base_url_parts.netloc and not url.startswith(base_url_parts.netloc) and url.startswith('//'):
                    url = 'file:' + url

    url_parts = urlsplit(url, scheme='file')
    if url_parts.scheme not in uses_relative:
        normalized_url = 'file:///{}'.format(url_parts.geturl())  # Eg. k:/Python/lib/....
    elif url_parts.scheme != 'file':
        normalized_url = urlunsplit((
            url_parts.scheme,
            url_parts.netloc,
            pathname2url(url_parts.path),
            url_parts.query,
            url_parts.fragment,
        ))
    elif os.path.isabs(url_parts.path):
        normalized_url = url_parts.geturl()
    elif keep_relative:
        # Can't use urlunsplit with a scheme because it converts relative paths to absolute ones.
        normalized_url = 'file:{}'.format(urlunsplit(('',) + url_parts[1:]))
    else:
        normalized_url = urlunsplit((
            url_parts.scheme,
            url_parts.netloc,
            os.path.abspath(url_parts.path),

normalized_url = 'file:///{}'.format(url_parts.geturl())  # Eg. k:/Python/lib/....
    elif url_parts.scheme != 'file':
        normalized_url = urlunsplit((
            url_parts.scheme,
            url_parts.netloc,
            pathname2url(url_parts.path),
            url_parts.query,
            url_parts.fragment,
        ))
    elif os.path.isabs(url_parts.path):
        normalized_url = url_parts.geturl()
    elif keep_relative:
        # Can't use urlunsplit with a scheme because it converts relative paths to absolute ones.
        normalized_url = 'file:{}'.format(urlunsplit(('',) + url_parts[1:]))
    else:
        normalized_url = urlunsplit((
            url_parts.scheme,
            url_parts.netloc,
            os.path.abspath(url_parts.path),
            url_parts.query,
            url_parts.fragment,
        ))
    return filter_url(normalized_url)

def add_trailing_slash(x):
        return urlunsplit((x[0], x[1], x[2] + '/' if x[2] and x[2][-1] != '/' else x[2], x[3], x[4]))

url_parts = urlsplit(url, scheme='file')
    if url_parts.scheme not in uses_relative:
        normalized_url = 'file:///{}'.format(url_parts.geturl())  # Eg. k:/Python/lib/....
    elif url_parts.scheme != 'file':
        normalized_url = urlunsplit((
            url_parts.scheme,
            url_parts.netloc,
            pathname2url(url_parts.path),
            url_parts.query,
            url_parts.fragment,
        ))
    elif os.path.isabs(url_parts.path):
        normalized_url = url_parts.geturl()
    elif keep_relative:
        # Can't use urlunsplit with a scheme because it converts relative paths to absolute ones.
        normalized_url = 'file:{}'.format(urlunsplit(('',) + url_parts[1:]))
    else:
        normalized_url = urlunsplit((
            url_parts.scheme,
            url_parts.netloc,
            os.path.abspath(url_parts.path),
            url_parts.query,
            url_parts.fragment,
        ))
    return filter_url(normalized_url)