Finish the method definition given below.
The method should determine the position of the word "Nemo" and return a string in the following manner: "I found Nemo at [position of the word nemo]!". If there are multiple instance of the word, the method should only return position for the first one. If Nemo is not found, the method should return "I can't find Nemo :(".
The search for Nemo should ignore cases.