code: def add_user_to_allow(self, name, user):
          
  
          # Clear user from both allow and deny before adding
          if not self.remove_user_from_acl(name, user):
              return False
  
          if name not in self._acl:
              return False
  
          self._acl[name]['allow'].append(user)
          return True
docs: Add a user to the given acl allow block.