text: """
  Wrapper for loading templates from the filesystem.
  """
  
  from django.conf import settings
  from django.template import TemplateDoesNotExist
  from django.utils._os import safe_join
  
  def get_template_sources(template_name, template_dirs=None):
      if not template_dirs:
          template_dirs = settings.TEMPLATE_DIRS
      for template_dir in template_dirs:
          try:
              yield safe_join(template_dir, template_name)
          except ValueError:
              # The joined path was located outside of template_dir.
              pass
  
  def load_template_source(template_name, template_dirs=None):
      tried = []
      for filepath in get_template_sources(template_name, template_dirs):
          try:
              return (open(filepath).read().decode(settings.FILE_CHARSET), filepath)
          except IOError:
              tried.append(filepath)
      if tried:
          error_msg = "Tried %s" % tried
      else:
          error_msg = "Your TEMPLATE_DIRS setting is empty. Change it to point to at least one template directory."
      raise TemplateDoesNotExist, error_msg
  load_template_source.is_usable = True
  