code: func (msp *bccspmsp) Validate(id Identity) error {
  	mspLogger.Debugf("MSP %s validating identity", msp.name)
  
  	switch id := id.(type) {
  	// If this identity is of this specific type,
  	// this is how I can validate it given the
  	// root of trust this MSP has
  	case *identity:
  		return msp.validateIdentity(id)
  	default:
  		return errors.New("identity type not recognized")
  	}
  }
docs: // Validate attempts to determine whether
  // the supplied identity is valid according
  // to this MSP's roots of trust; it returns
  // nil in case the identity is valid or an
  // error otherwise