old_contents: from django.conf import settings
  from django.core.exceptions import ImproperlyConfigured
  
  from cms.utils.compat.dj import is_installed as app_is_installed
  
  
  def validate_dependencies():
      """
      Check for installed apps, their versions and configuration options
      """
      if not app_is_installed('mptt'):
          raise ImproperlyConfigured('django CMS requires django-mptt package.')
  
      if not app_is_installed('reversion'):
          from reversion.admin import VersionAdmin
          if not hasattr(VersionAdmin, 'get_urls'):
              raise ImproperlyConfigured('django CMS requires newer version of reversion (VersionAdmin must contain get_urls method)')
  
  
  def validate_settings():
      """
      Check project settings file for required options
      """
      if 'django.core.context_processors.request' not in settings.TEMPLATE_CONTEXT_PROCESSORS:
          raise ImproperlyConfigured('django CMS requires django.core.context_processors.request in settings.TEMPLATE_CONTEXT_PROCESSORS to work correctly.')
  
  
  def setup():
      """
      Gather all checks and validations
      """
      validate_dependencies()
      validate_settings()
  
new_contents: from django.conf import settings
  from django.core.exceptions import ImproperlyConfigured
  
  from cms.utils.compat.dj import is_installed as app_is_installed
  
  
  def validate_dependencies():
      """
      Check for installed apps, their versions and configuration options
      """
      if not app_is_installed('mptt'):
          raise ImproperlyConfigured('django CMS requires django-mptt package.')
  
      if app_is_installed('reversion'):
          from reversion.admin import VersionAdmin
          if not hasattr(VersionAdmin, 'get_urls'):
              raise ImproperlyConfigured('django CMS requires newer version of reversion (VersionAdmin must contain get_urls method)')
  
  
  def validate_settings():
      """
      Check project settings file for required options
      """
      if 'django.core.context_processors.request' not in settings.TEMPLATE_CONTEXT_PROCESSORS:
          raise ImproperlyConfigured('django CMS requires django.core.context_processors.request in settings.TEMPLATE_CONTEXT_PROCESSORS to work correctly.')
  
  
  def setup():
      """
      Gather all checks and validations
      """
      validate_dependencies()
      validate_settings()
  
subject: Fix typo