def get_aside_from_xblock(xblock, aside_type):
    """
    Gets an instance of an XBlock aside from the XBlock that it's decorating. This also
    configures the aside instance with the runtime and fields of the given XBlock.

    Args:
        xblock (xblock.core.XBlock): The XBlock that the desired aside is decorating
        aside_type (str): The aside type

    Returns:
        xblock.core.XBlockAside: Instance of an xblock aside
    """
    return xblock.runtime.get_aside_of_type(xblock, aside_type)