capybara/virtualenv/lib/python2.7/site-packages/pip/_vendor/pkg_resources/__init__.py
def find_eggs_in_zip(importer, path_item, only=False):
    """
    Find eggs in zip files; possibly multiple nested eggs.
    """
    if importer.archive.endswith('.whl'):
        # wheels are not supported with this finder
        # they don't have PKG-INFO metadata, and won't ever contain eggs
        return
    metadata = EggMetadata(importer)
    if metadata.has_metadata('PKG-INFO'):
        yield Distribution.from_filename(path_item, metadata=metadata)
    if only:
        # don't yield nested distros
        return
    for subitem in metadata.resource_listdir('/'):
        if subitem.endswith('.egg'):
            subpath = os.path.join(path_item, subitem)
            for dist in find_eggs_in_zip(zipimport.zipimporter(subpath), subpath):
                yield dist
def find_eggs_in_zip(importer, path_item, only=False):
    """
    Find eggs in zip files; possibly multiple nested eggs.
    """
    if importer.archive.endswith('.whl'):
        # wheels are not supported with this finder
        # they don't have PKG-INFO metadata, and won't ever contain eggs
        return
    metadata = EggMetadata(importer)
    if metadata.has_metadata('PKG-INFO'):
        yield Distribution.from_filename(path_item, metadata=metadata)
    if only:
        # don't yield nested distros
        return
    for subitem in metadata.resource_listdir('/'):
        if subitem.endswith('.egg'):
            subpath = os.path.join(path_item, subitem)
            for dist in find_eggs_in_zip(zipimport.zipimporter(subpath), subpath):
                yield dist
Find eggs in zip files; possibly multiple nested eggs.