introducedDefensiveThreeSeconds

Given a predicate that represents a relationship or action between entities, generate a one-sentence description explaining its meaning.  
# Instructions
Focus on describing the relationship, not the entities themselves. 
# Response Format
Begin the description with \' Indicates...\'

Predicate: introducedDefensiveThreeSeconds

Indicates that an entity (such as a league or rules committee) instituted the defensive three-second rule, establishing a restriction on how long defenders may remain in the key.