code: def execute
        File.open(@outfile, 'w') do |out|
          File.open(@infile, 'r').each_with_index do |line, index|
            line = line.chomp
  
            next if line.empty?
            
            line = unstring(line).chomp
  
            extraction = col_filter.process(row_filter.process(line, row: index))
  
            next unless extraction
  
            key = @key_filter.process(line)
            
            unless @keys.include? key
              out.puts extraction
              @keys << key
            end
          end
        end
      end
docs: Creates a new Unique
     Sycsvpro::Unique.new(infile: "infile.csv",
                          outfile: "outfile.csv",
                          rows:    "1,3-4",
                          cols:    "0,2,4-6",
                          key:     "0,1").execute
   Removes the duplicates from infile and writes the result to outfile