def METHOD_NAME(dist, req):
    """Fetch an egg needed for building.
    Legacy path using EasyInstall.
    """
    tmp_dist = dist.__class__({'script_args': ['easy_install']})
    opts = tmp_dist.get_option_dict('easy_install')
    opts.clear()
    opts.update(
        (k, v)
        for k, v in dist.get_option_dict('easy_install').items()
        if k in (
            # don't use any other settings
            'find_links', 'site_dirs', 'index_url',
            'optimize', 'site_dirs', 'allow_hosts',
        ))
    if dist.dependency_links:
        links = dist.dependency_links[:]
        if 'find_links' in opts:
            links = _fixup_find_links(opts['find_links'][1]) + links
        opts['find_links'] = ('setup', links)
    install_dir = dist.get_egg_cache_dir()
    cmd = easy_install(
        tmp_dist, args=["x"], install_dir=install_dir,
        exclude_scripts=True,
        always_copy=False, build_directory=None, editable=False,
        upgrade=False, multi_version=True, no_report=True, user=False
    )
    cmd.ensure_finalized()
    return cmd.easy_install(req)