code: func (c *CredentialsStore) Check(username, password string) bool {
  	pw, ok := c.store[username]
  	if !ok {
  		return false
  	}
  	return password == pw ||
  		bcrypt.CompareHashAndPassword([]byte(pw), []byte(password)) == nil
  }
docs: // Check returns true if the password is correct for the given username.