Delete a group policy.

    CLI Example::

    .. code-block:: bash

        salt myminion boto_iam.delete_group mygroup

def delete_group(group_name, region=None, key=None,
                        keyid=None, profile=None):
    '''
    Delete a group policy.

    CLI Example::

    .. code-block:: bash

        salt myminion boto_iam.delete_group mygroup
    '''
    conn = _get_conn(region=region, key=key, keyid=keyid, profile=profile)
    if not conn:
        return False
    _group = get_group(
        group_name, region, key, keyid, profile
    )
    if not _group:
        return True
    try:
        conn.delete_group(group_name)
        log.info('Successfully deleted IAM group %s.', group_name)
        return True
    except boto.exception.BotoServerError as e:
        log.debug(e)
        log.error('Failed to delete IAM group %s.', group_name)
        return False