What is the relationship between Polly Pocket and Mattel in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

Mattel Girls & Boys Brands-including Barbie fashion dolls and accessories ("Barbie"), Monster High, Disney Classics, Ever After High, Little Mommy, and Polly Pocket (collectively "Other Girls"), Hot Wheels and Matchbox vehicles and play sets (collectively "Wheels"), and CARS, Disney Planes, BOOMco, Radica, Toy Story, Max Steel, WWE Wrestling, Batman, and games and puzzles (collectively "Entertainment").

Answer: distributed_by