Final answer:
The technique described in your question is the concept of flashback, not irony. Flashback is when an author interrupts the storyline to look back at past events. Irony, however, is when the outcome is different from what was expected.
Step-by-step explanation:
The statement in your question is actually defining a literary technique called flashback, not irony. Flashback is indeed the interruption in the present action of the plot to show events that happened at an earlier time. It's used by authors to provide background information or insight about a character or events. On the other hand, irony is a literary device that signifies the difference between what is expected to happen and what actually happens. It comes in several forms including dramatic irony, situational irony, and verbal irony.
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