title: How to force Django Admin to save the inline?
body: <p>I have an app who uses Django Inline Admin.</p>
  
  <pre><code>from django.db import models
  
  class MyClass(models.Model):
      field1 = models.CharField(max_length=128)
      fieldN = models.IntegerField()
  
  class MyInlineClass(models.Model):
      field1 = models.CharField(max_length=128)
      field2 = models.ForeignKey(MyClass)
      fieldN = models.IntegerField()
  
      def save(self, force_insert=False, force_update=False, using=None, update_fields=None):
          if self.field2:
              self.field1 = self.field2.field1
          return BaseModel.save(self, force_insert=force_insert, force_update=force_update, using=using, update_fields=update_fields)
  </code></pre>
  
  <p>For reasons beyond my control, the fieldN is repeated in MyClass and in MyInlineClass.</p>
  
  <p>So the user has to change the fieldN on MyClass and on eachone of the inlines.</p>
  
  <p>I want to save fieldN on the inline when changing fieldN on my admin class.</p>
  
  <pre><code>from django.contrib import admin
  
  class MyInlineClassInline(admin.TabularInline):
      model = MyInlineClass
      fields = ['field2']
  
  class MyClassAdmin(admin.ModelAdmin):
      inlines = [MyInlineClassInline,]
  </code></pre>
  
  <p>If I override the MyClass save method, how could I force to call MyInlineClass save method also?</p>
  
  <p>Any thoughts?</p>