code: func (a *ACL) Bootstrap() (*ACLToken, *WriteMeta, error) {
  	r := a.c.newRequest("PUT", "/v1/acl/bootstrap")
  	rtt, resp, err := requireOK(a.c.doRequest(r))
  	if err != nil {
  		return nil, nil, err
  	}
  	defer resp.Body.Close()
  
  	wm := &WriteMeta{RequestTime: rtt}
  	var out ACLToken
  	if err := decodeBody(resp, &out); err != nil {
  		return nil, nil, err
  	}
  	return &out, wm, nil
  }
docs: // Bootstrap is used to perform a one-time ACL bootstrap operation on a cluster
  // to get the first management token.