input: Write a function to create a Django application with a model that stores the name, address, and email of a user. The function should perform the following steps: create a Django project, define the User model, and perform database migrations. If successful, the function should return a message indicating that the app and model have been created successfully. If an error occurs, the function should return an error message.
  assert create_django_app() == "Django app 'myapp' and User model created successfully."
  assert create_django_app() == "Django app 'anotherapp' and User model created successfully."
  assert create_django_app() == "Error: Django project creation failed."
  assert create_django_app() == "Error: Model definition failed."
  assert create_django_app() == "Error: Database migration failed."
output: 
  def create_django_app():
      try:
          import os
          from django.core.management import execute_from_command_line
          from django.core.management.base import CommandError
          from django.db import models
  
          # Create Django project
          try:
              execute_from_command_line(["django-admin", "startproject", "myproject"])
          except CommandError:
              return "Error: Django project creation failed."
  
          # Change to project directory
          os.chdir("myproject")
  
          # Create Django app
          try:
              execute_from_command_line(["python", "manage.py", "startapp", "myapp"])
          except CommandError:
              return "Error: Django app creation failed."
  
          # Define User model
          try:
              with open("myapp/models.py", "w") as f:
                  f.write("""
  from django.db import models
  
  class User(models.Model):
      name = models.CharField(max_length=100)
      address = models.CharField(max_length=200)
      email = models.EmailField()
  """)
          except Exception:
              return "Error: Model definition failed."
  
          # Perform database migrations
          try:
              execute_from_command_line(["python", "manage.py", "makemigrations", "myapp"])
              execute_from_command_line(["python", "manage.py", "migrate"])
          except CommandError:
              return "Error: Database migration failed."
  
          return "Django app 'myapp' and User model created successfully."
      except Exception as e:
          return f"Error: {str(e)}"
  