def check
      links = []
      read_file.each do |key, value|
        value["checked"] = Time.now
        if value["total"] < value["min"]
          puts "You're running low on #{key}!"
          links << key
        end
      end
      links.uniq!
      links.each { |link| buy(link)}
    end
def check
      links = []
      read_file.each do |key, value|
        value["checked"] = Time.now
        if value["total"] < value["min"]
          puts "You're running low on #{key}!"
          links << key
        end
      end
      links.uniq!
      links.each { |link| buy(link)}
    end
Checks the total number of items on hand against their acceptable minimum values and opens the URLs of any items running low in stock.
 @return Opens a link in default web browser if URL is set for low stock item