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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def is_admin(controller, client, actor):
 """Used to determine whether someone issuing a command is an admin. By default, checks to see if there's a line of the type nick=host that matches the command's actor in the [admins] section of the config file, or a key that matches the entire mask (e.g. "foo@bar" or "foo@bar=1"). """

    config = controller.config
    if not config.has_section("admins"):
        logging.debug("Ignoring is_admin check - no [admins] config found.")
        return False
    for key,val in config.items("admins"):
        if actor == User(key):
            logging.debug("is_admin: %r matches admin %r", actor, key)
            return True
        if actor.nick.lower() == key.lower() and actor.host.lower() == val.lower():
            logging.debug("is_admin: %r matches admin %r=%r", actor, key, val)
            return True
    logging.debug("is_admin: %r is not an admin.", actor)
    return False