code: func NewManagerWithPublicKey(id string, key *rsa.PublicKey) Manager {
  	return &tokenManager{
  		publicKeysMap: map[string]*rsa.PublicKey{id: key},
  		publicKeys:    []*PublicKey{{KeyID: id, Key: key}},
  	}
  }
docs: // NewManagerWithPublicKey returns a new token Manager for handling tokens with the only public key