code: def init_key_columns(key_scheme)
  
          @key_titles  = []
          @key_columns = []
  
          keys = key_scheme.scan(/(\d+):(\w+)/)
  
          keys.each do |key|
            @key_titles  << key[1]
            @key_columns << key[0].to_i
          end
  
        end
docs: Initialize the key columns and headers