Mayor Of London Boris Johnson Speaks At A Crossrail Event [Getty Images]

Boris Johnson, mayor of London, speaks during an event to announce the plans for Crossrail 2 railway project, in London, U.K., on Friday, July, 17, 2015. Johnson discussed the proposed 20 billion pounds ($31 billion) Crossrail 2 rail line through London from north of the capital in Hertfordshire to Surrey in the south. Photographer: Chris Ratcliffe/Bloomberg via Getty Images

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