Add initial file for GPS 2.3
user
```ruby
# Your Names
# 1)Catie Stallings
# 2)

# We spent [#] hours on this challenge.

# Bakery Serving Size portion calculator.

def serving_size_calc(item_to_make, num_of_ingredients)
  library = {"cookie" => 1, "cake" =>  5, "pie" => 7}
  error_counter = 3

  library.each do |food|
    if library[food] != library[item_to_make]
      error_counter += -1
    end
  end

  if error_counter > 0
    raise ArgumentError.new("#{item_to_make} is not a valid input")
  end

  serving_size = library.values_at(item_to_make)[0]
  remaining_ingredients = num_of_ingredients % serving_size

  case remaining_ingredients
  when 0
    return "Calculations complete: Make #{num_of_ingredients / serving_size} of #{item_to_make}"
  else
    return "Calculations complete: Make #{num_of_ingredients / serving_size} of #{item_to_make}, you have #{remaining_ingredients} leftover ingredients. Suggested baking items: TODO: MAKE THIS FEATURE"
  end
end

p serving_size_calc("pie", 7)
p serving_size_calc("pie", 8)
p serving_size_calc("cake", 5)
p serving_size_calc("cake", 7)
p serving_size_calc("cookie", 1)
p serving_size_calc("cookie", 10)
p serving_size_calc("THIS IS AN ERROR", 5)

#  Reflection
```
assistant