Used for changing the topic or bringing up a new topic; 'by the way', 'speaking of'.
Long explanation:
The ところで (tokorode) grammar point is used to change the topic of conversation or introduce a new topic. It can be translated as 'by the way' or 'speaking of' in English. It is often used when the speaker wants to ask a question or share some information on a different subject. It can be placed at the beginning or in the middle of a sentence.