Return a dist_factory for a path_item and entry

def dist_factory(path_item, entry, only):
    """
    Return a dist_factory for a path_item and entry
    """
    lower = entry.lower()
    is_meta = any(map(lower.endswith, ('.egg-info', '.dist-info')))
    return (
        distributions_from_metadata
        if is_meta else
        find_distributions
        if not only and _is_egg_path(entry) else
        resolve_egg_link
        if not only and lower.endswith('.egg-link') else
        NoDists()
    )