code: func (msp *bccspmsp) getCertificationChainForBCCSPIdentity(id *identity) ([]*x509.Certificate, error) {
  	if id == nil {
  		return nil, errors.New("Invalid bccsp identity. Must be different from nil.")
  	}
  
  	// we expect to have a valid VerifyOptions instance
  	if msp.opts == nil {
  		return nil, errors.New("Invalid msp instance")
  	}
  
  	// CAs cannot be directly used as identities..
  	if id.cert.IsCA {
  		return nil, errors.New("An X509 certificate with Basic Constraint: " +
  			"Certificate Authority equals true cannot be used as an identity")
  	}
  
  	return msp.getValidationChain(id.cert, false)
  }
docs: // getCertificationChainForBCCSPIdentity returns the certification chain of the passed bccsp identity within this msp