code: func (c *IdentityConfig) CAClientCert(org string) ([]byte, bool) {
  	caConfigs, ok := c.caConfigsByOrg[strings.ToLower(org)]
  	if ok {
  		//for now, we're only loading the first Cert Authority by default.
  		return caConfigs[0].TLSCAClientCert, true
  	}
  
  	return nil, false
  }
docs: //CAClientCert read configuration for the fabric CA client cert bytes for given org