How to import walks from JSON file

walk.rb

class Walk < ApplicationRecord
  has_many :photos

  def self.import
    file = File.read('./walks-in-victoria.json')
    walks = JSON.parse(file)
    walks.each do |w|
      walk = Walk.create(title: w['title'], grade: w['grade'], 
        grade_note: w['gradeNote'], encoded_line: w['encodedLine'])
      w['images'].each do |image_url|
        walk.photos.create(url: image_url)
      end
    end    
  end
end