# File lib/active_support/core_ext/time/calculations.rb, line 16
          def days_in_month(month, year=nil)
            if month == 2
              !year.nil? && (year % 4 == 0) && ((year % 100 != 0) || (year % 400 == 0)) ?  29 : 28
            elsif month <= 7
              month % 2 == 0 ? 30 : 31
            else
              month % 2 == 0 ? 31 : 30
            end
          end