undefined local variable or method - method receiving (holiday_hash), but inside code you were using holiday_supplies.

[cunhasb]

def all_winter_holiday_supplies(holiday_hash)
holiday_supplies[:winter].map do |holiday, supplies|
supplies
end.flatten
end

def all_supplies_in_holidays(holiday_hash)
holiday_supplies.each do |season, holidays|
puts "#{season.capitalize}:"
holidays.each do |holiday, supplies|
puts" #{holiday.to_s.split('_').map {|w| w.capitalize }.join(' ') }: #{supplies.join(", ")}"
end
end
end