Question: Who released the 2015 animated short film which is a inspiration Frozen Ever After in Epcot at the Walt Disney World Resort?

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Walt Disney World International Program: The Walt Disney World International Program is an international internship program sponsored and operated by The Walt Disney Company at the Walt Disney World Resort in Lake Buena Vista, Florida, in the United States.  The Walt Disney World International Program recruits participants (18 years and older) from outside the United States for year-long cultural exchanges with paid positions and summer-long paid internships working at the Walt Disney World Resort.

Frozen Fever: Frozen Fever is a 2015 American computer-animated musical fantasy short film produced by Walt Disney Animation Studios and released by Walt Disney Pictures.  It is a sequel to the 2013 feature film "Frozen", and tells the story of Anna's birthday party given by Elsa with the help of Kristoff, Sven, and Olaf.  Chris Buck and Jennifer Lee again served as the directors with Kristen Bell, Idina Menzel, Jonathan Groff, and Josh Gad providing the lead voices.

Walt Disney World Swan: The Walt Disney World Swan is a resort hotel designed by architect Michael Graves located between Epcot and Disney's Hollywood Studios behind Disney's BoardWalk Resort and across from its sister resort, the Walt Disney World Dolphin.  The Swan, which opened January 13, 1990 on Disney property, is a joint venture between the Walt Disney Company, Tishman Hotel Corporation, MetLife and Starwood Hotels and Resorts.  The land the resort occupies is owned by the Walt Disney Company, while the buildings themselves are leased by Disney to the Tishman Hotel Corporation and MetLife and operated by Starwood Hotels & Resorts Worldwide under the Westin brand.  The Walt Disney World Swan and Dolphin are a part of the Walt Disney Collection of resorts, because of this they are Disney branded and guests of the resort have access to special Disney benefits available to Disney Resort Hotel guests only.

Epcot: Epcot (originally named EPCOT Center) is a theme park at the Walt Disney World Resort in Bay Lake, Florida.  It is owned and operated by the Walt Disney Company through its Parks and Resorts division.  Inspired by an unrealized concept developed by Walt Disney, the park opened on October 1, 1982 and was the second of four theme parks built at Walt Disney World, after the Magic Kingdom.  Spanning 300 acres , more than twice the size of the Magic Kingdom park, Epcot is dedicated to the celebration of human achievement, namely technological innovation and international culture, and is often referred to as a "permanent world's fair".  The park is divided into two sections: Future World, made up of eight pavilions, and World Showcase, themed to 11 world nations.

Summer Nightastic!: Summer Nightastic!  was an annual three-month promotion by the Walt Disney Company celebrating the summer at the US Disney Resorts.  It started in 2009 at the Disneyland Resort and had returned for 2010 at the Disneyland Resort and at the Walt Disney World Resort.  The event included special nighttime events and ride operations.  Walt Disney World featured events at the Magic Kingdom, Disney's Hollywood Studios, and Epcot.  The Disneyland Resort featured events at Disneyland Park and Disney California Adventure Park.  It was replaced by Disney Soundsational Summer at Disneyland, however the fireworks were retained.  The event did not return to Walt Disney World in 2011 either.

Walt Disney World Dolphin: The Walt Disney World Dolphin is a resort hotel designed by architect Michael Graves located between Epcot and Disney's Hollywood Studios in the Walt Disney World Resort in Bay Lake, Florida, next to Disney's BoardWalk Resort area.  It opened on June 1, 1990 and is joined to its sister hotel, the Walt Disney World Swan (also designed by Graves) by a palm-tree lined covered walkway crossing a lagoon.  The Walt Disney World Swan and Dolphin is a joint venture between the Walt Disney Company, Tishman Hotel Corporation, MetLife and Starwood Hotels and Resorts.  The land the resort occupies is owned by the Walt Disney Company, while the buildings themselves are leased by Disney to the Tishman Hotel Corporation and MetLife but operated by Starwood Hotels & Resorts Worldwide under the Sheraton Hotels brand.  The Walt Disney World Swan and Dolphin are a part of the Walt Disney Collection of resorts; because of this they are Disney branded and guests of the resort have access to special Disney benefits available to Disney Resort Hotel guests only.

Gran Fiesta Tour Starring The Three Caballeros: Gran Fiesta Tour Starring The Three Caballeros is a musical dark boat ride housed within the pyramid-shaped Mexico Pavilion, at the Epcot theme park at the Walt Disney World Resort in Florida.  It was the first World Showcase attraction to feature Disney characters based on an existing property.  Norway followed suit in 2014 when it closed its Maelstrom ride to make room for Frozen Ever After, which opened in 2016.

Walt Disney World Monorail System: The Walt Disney World Monorail System is a public transit monorail system in operation at the Walt Disney World Resort in Bay Lake, Florida, near Orlando.  The Walt Disney World Resort currently operates twelve Mark VI monorail trains on three lines of service.  The monorail system opened in 1971 with two routes (Magic Kingdom: Resort and Express) and with Mark IV monorail trains.  It was expanded to three lines (Magic Kingdom: Resort and Express, plus Epcot) in 1982, and the rolling stock was updated to Mark VI trains in 1989.

Disney's All-Star Music Resort: Disney's All-Star Music Resort is a resort that is part of the Walt Disney World Resort.  It is one of five resorts in the Value Resort category, along with Disney's All-Star Sports Resort, Disney's All-Star Movies Resort, Disney's Pop Century Resort, and Disney's Art of Animation Resort.  The resort is located on the southern portion of the Walt Disney World Resort property near Disney's Animal Kingdom.  Disney's All-Star Music Resort is a 1,604-room hotel featuring giant icons that pay homage to classic music genres—including Broadway show tunes, calypso, country, jazz, and rock n' roll.  Disney's All-Star Music Resort was the first Disney Value Resort with family suites.  As a characteristic with all Disney Value resorts, the resort features a music theme with giant novelty items such as guitars, trumpets, and drums.  The resort is designated in the Florida Green Lodging Program.

Frozen Ever After: Frozen Ever After is a dark water ride attraction in Epcot at the Walt Disney World Resort.  Part of the Norway Pavilion of the park's World Showcase section, the attraction features scenes inspired by Disney's 2013 animated film "Frozen" as well as the 2015 animated short "Frozen Fever".  It opened on June 21, 2016 and replaced the former Maelstrom attraction, utilizing the same ride vehicles and a similar track layout.

Supporting paragraphs: Frozen Ever After Frozen Fever
Answer: Walt Disney Pictures