+    @classmethod
+    def publish(cls, infile):
+        from librarian.parser import WLDocument
+        from django.core.files.base import ContentFile
+        xml = infile.get_string()
+        wldoc = WLDocument.from_string(xml)
+
+        try:
+            lessons = [Lesson.objects.get(slug=part.slug)
+                        for part in wldoc.book_info.parts]
+        except Lesson.DoesNotExist, e:
+            raise cls.IncompleteError(part.slug)
+
+        slug = wldoc.book_info.url.slug
+        try:
+            section = cls.objects.get(slug=slug)
+        except cls.DoesNotExist:
+            section = cls(slug=slug, order=0)
+
+        # Save XML file
+        section.xml_file.save('%s.xml' % slug, ContentFile(xml), save=False)
+        section.title = wldoc.book_info.title
+        section.save()
+
+        section.lesson_set.all().update(section=None)
+        for i, lesson in enumerate(lessons):
+            lesson.section = section
+            lesson.order = i
+            lesson.save()
+
+        return section
+
+    def syntetic_lesson(self, level):