title: ValueError - Python Django
body: <p>I went through forums and did some changes in my codes but the problem is still there. I did migrate and makemigrations, and even deleted migrate and recreate it again.</p>
  
  <p>I also added default=0 to the models.py code:</p>
  
  <blockquote>
    <p>age = models.PositiveIntegerField(default=0)</p>
  </blockquote>
  
  <p>I'll appreciate you if you help me on this issue.
  These are some lines of codes, let me know if you need any other information.</p>
  
  <p><strong>This is the error:</strong></p>
  
  <pre><code>ValueError at /basic_app/create/
  invalid literal for int() with base 10: 'create'
  Request Method: GET
  Request URL:    http://127.0.0.1:8000/basic_app/create/
  Django Version: 2.1.2
  Exception Type: ValueError
  Exception Value:    
  invalid literal for int() with base 10: 'create'
  Exception Location: C:\ProgramData\Miniconda3\envs\myDjanEnv\lib\site-packages\django\db\models\fields\__init__.py in get_prep_value, line 965
  Python Executable:  C:\ProgramData\Miniconda3\envs\myDjanEnv\python.exe
  Python Version: 3.7.0
  Python Path:    
  ['C:\\Users\\Administrator\\Desktop\\django_lecture\\djan_advance\\advcbv',
   'C:\\ProgramData\\Miniconda3\\envs\\myDjanEnv\\python37.zip',
   'C:\\ProgramData\\Miniconda3\\envs\\myDjanEnv\\DLLs',
   'C:\\ProgramData\\Miniconda3\\envs\\myDjanEnv\\lib',
   'C:\\ProgramData\\Miniconda3\\envs\\myDjanEnv',
   'C:\\ProgramData\\Miniconda3\\envs\\myDjanEnv\\lib\\site-packages']
  </code></pre>
  
  <p><strong>This is __init__.py file, line 960-965:</strong></p>
  
  <blockquote>
  <pre><code>def get_prep_value(self, value):
      from django.db.models.expressions import OuterRef
      value = super().get_prep_value(value)
      if value is None or isinstance(value, OuterRef):
          return value
      return int(value)
  </code></pre>
  </blockquote>
  
  <p><strong>The models.py file:</strong></p>
  
  <pre><code>from django.db import models
  
  # Create your models here.
  class School(models.Model):
      name = models.CharField(max_length=128)
      principal = models.CharField(max_length=128)
      location = models.CharField(max_length=128)
  
      def __str__(self):
          return self.name
  
  class Student(models.Model):
      name = models.CharField(max_length=128)
      age = models.PositiveIntegerField()
      school = models.ForeignKey(School,related_name='students',on_delete=models.PROTECT)
  
      def __str__(self):
          return self.name
  </code></pre>
  
  <p><strong>urls.py file in basic_app folder:</strong></p>
  
  <pre><code>from django.conf.urls import url
  from basic_app import views
  
  app_name = 'basic_app'
  
  urlpatterns = [
      url(r'^$',views.schoolListView.as_view(),name='list'),
      url(r'^(?P&lt;pk&gt;[-\w]+)/$',views.schoolDetailView.as_view(),name='detail'),
      url(r'^create/$',views.schoolCreateView.as_view(),name='create')
  ]
  </code></pre>
  
  <p><strong>views.py file:</strong></p>
  
  <pre><code>from django.shortcuts import render
  from django.views.generic import (View,TemplateView,
                                  ListView,DetailView,
                                  CreateView,UpdateView,
                                  DeleteView)
  from . import models
  
  class IndexView(TemplateView):
      template_name = 'index.html'
  
  class schoolListView(ListView):
      context_object_name = 'schools'
      model = models.School
  
  class schoolDetailView(DetailView):
      context_object_name = 'school_detail'
      model = models.School
      template_name = 'basic_app/school_detail.html'
  
  class schoolCreateView(CreateView):
      fields = ('name','principal','location')
      model = models.School
  </code></pre>