def actions(self, state):
        """Return the actions that can be executed in the given state.
        The result would be a list, since there are only four possible actions
        in any given state of the environment."""
       
        possible_actions = list()
        index_blank_square = self.find_blank_square(state)

        if index_blank_square(0) == 0:
            possible_actions += ['DOWN']
        elif index_blank_square(0) == 1:
            possible_actions += ['UP', 'DOWN']
        elif index_blank_square(0) == 2:
            possible_actions += ['UP']
        
        if index_blank_square(1) == 0:
            possible_actions += ['RIGHT']
        elif index_blank_square(1) == 1:
            possible_actions += ['LEFT', 'RIGHT']
        elif index_blank_square(1) == 2:
            possible_actions += ['LEFT']

        return possible_actions