code: func (c *CredentialsStore) HasPerm(username string, perm string) bool {
  	m, ok := c.perms[username]
  	if !ok {
  		return false
  	}
  
  	if _, ok := m[perm]; !ok {
  		return false
  	}
  	return true
  }
docs: // HasPerm returns true if username has the given perm. It does not
  // perform any password checking.