[] (TimeZone)

    # File lib/active_support/values/time_zone.rb, line 376
        def [](arg)
          case arg
            when String
              ZONES_MAP[arg]
            when Numeric, ActiveSupport::Duration
              arg *= 3600 if arg.abs <= 13
              all.find { |z| z.utc_offset == arg.to_i }
            else
              raise ArgumentError, "invalid argument to TimeZone[]: #{arg.inspect}"
          end
        end