my_callbacks_wrong.erl:26: The return type 
          #state{parent :: pid(),
                 status :: 'closed' | 'init' | 'open',
                 subscribe :: [{pid(), integer()}],
                 counter :: integer()} in the specification of callback_init/1 is not a subtype of 
          {'ok', _}, which is the expected return type for the callback of the my_behaviour behaviour
my_callbacks_wrong.erl:28: The inferred return type of callback_init/1 
         (#state{parent :: pid(),
                 status :: 'init',
                 subscribe :: [],
                 counter :: 1}) has nothing in common with 
          {'ok', _}, which is the expected return type for the callback of the my_behaviour behaviour
my_callbacks_wrong.erl:30: The return type 
          {'reply',
           #state{parent :: pid(),
                  status :: 'closed' | 'init' | 'open',
                  subscribe :: [{pid(), integer()}],
                  counter :: integer()}} in the specification of callback_cast/3 is not a subtype of 
          {'noreply', _}, which is the expected return type for the callback of the my_behaviour behaviour
my_callbacks_wrong.erl:39: The specified type for the 2nd argument of callback_call/3 (
          atom()) is not a supertype of 
          pid(), which is expected type for this argument in the callback of the my_behaviour behaviour