Specifying Units in Django -

i'm creating small app counts calories in recipes. i'm curious know if there better way this. each recipe has ingredients. each ingredient has amount, weight, , calorie profile.

so instance:

• recipe: flourless nutella cake
  • ingredient: eggs
    • amount: 4
    • weight: large eggs (could cups or oz or whatever)
    • calories: 312 (calculated amount * weight)
  • ingredient: nutella
    • amount: 8.5
    • weight: ounces
    • calories: 850

here models.py:

from foodlist.models import food, weight

class ingredient(models.model):

food = models.foreignkey(food)
weight = models.foreignkey(weight)
amount = models.floatfield(default=1.0)

...

class recipe(models.model):

ingredients = models.manytomanyfield(ingredient, blank=true, null=true)

...

the problem every time want make new recipe different amount of eggs, first have make new ingredient containing correct amount of eggs. have 1 ingredient says "4 large eggs" , ingredient says "2 large eggs."

i'm using inlines in admin see together, still seems rather cumbersome , there better way.

is there way can under recipe instead of intermediate step in ingredient?

remove amount field ingredients model, , create new model this:

class amount(models.model):     units = model.integerfield(default=1)     ingredient = models.foreignkey(ingredient)     recipe = models.foreignkey(recipe) 

as long keep amounts separate ingredients model, can put ingredients in , track amounts using "units" field each recipe.