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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_action_token(self, type_=None, action_token=None):
 """Set action tokens type_ -- either "upload" or "image" action_token -- string obtained from user/get_action_token, set None to remove the token """

        if action_token is None:
            del self._action_tokens[type_]
        else:
            self._action_tokens[type_] = action_token