text: const Cost = require('./cost')
  
  class Building {
      name
      castle_name
      level
      cost
      requirements
      constructor({
          name = '',
          castle_name = '',
          level = 0,
          cost = new Cost(),
          requirements = [],
          last_date_modified = new Date()
      }={}) {
          this.name = name
          this.castle_name = castle_name
          this.level = level
          this.cost = cost
          this.requirements = requirements
          this.last_date_modified = last_date_modified
      }
  }
  
  module.exports = Building