def find_same_occurence
      selected = @candidates.select { |delim, count|
        begin
          CSV.parse(@sample, col_sep: delim).select{|e| !e.empty? }.map{|e| e.count}.uniq.count == 1
        rescue Exception => ex
          false
        end
      }.keys

      return selected.first if selected.count == 1
      return DEFAULT_DELIMITER if selected.include?(DEFAULT_DELIMITER)
    end
def find_same_occurence
      selected = @candidates.select { |delim, count|
        begin
          CSV.parse(@sample, col_sep: delim).select{|e| !e.empty? }.map{|e| e.count}.uniq.count == 1
        rescue Exception => ex
          false
        end
      }.keys

      return selected.first if selected.count == 1
      return DEFAULT_DELIMITER if selected.include?(DEFAULT_DELIMITER)
    end
high confident level