def add_source_link_to_description(description: str, link: str) ->str:
    """Add the source ticket URL to the description.

    Args:
        description: The original ticket's description.
        link: The URL to the source ticket.

    Returns:
        The modified description for the ticket.
    """
    link_message = '<This ticket was migrated from %s>' % link
    if description:
        link_message += '\r\n\r\n'
    return link_message + description
