Check to see if an ELB exists.

    CLI example:

    .. code-block:: bash

        salt myminion boto_elb.exists myelb region=us-east-1

def exists(name, region=None, key=None, keyid=None, profile=None):
    '''
    Check to see if an ELB exists.

    CLI example:

    .. code-block:: bash

        salt myminion boto_elb.exists myelb region=us-east-1
    '''
    conn = _get_conn(region=region, key=key, keyid=keyid, profile=profile)

    try:
        elb = conn.get_all_load_balancers(load_balancer_names=[name])
        if elb:
            return True
        else:
            log.debug('The load balancer does not exist in region %s', region)
            return False
    except boto.exception.BotoServerError as error:
        log.warning(error)
        return False