New in Swift 3:
• Swift-enhanced API for Grand Central Dispatch and Core Graphics
• Uniform API style across all of Swift 3, including frameworks in the platform SDKs
• Playgrounds support for open source toolchains from Swift.org
• Xcode migrators help move your existing Swift code to Swift 3
• Swift 2.3 aids the transition to Swift 3 while providing access to the latest SDKs
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