-def add_to_manifest(manifest, partno):
-    """ Adds a node to the manifest section in content.opf file """
-
-    partstr = 'part%d' % partno
-    e = manifest.makeelement(
-        OPFNS('item'), attrib={'id': partstr, 'href': partstr + '.html',
-                               'media-type': 'application/xhtml+xml'}
-    )
-    manifest.append(e)
-
-
-def add_to_spine(spine, partno):
-    """ Adds a node to the spine section in content.opf file """
-
-    e = spine.makeelement(
-        OPFNS('itemref'),
-        attrib={'idref': 'part%d' % partno}
-    )
-    spine.append(e)
-
-
-class TOC(object):
-    def __init__(self, name=None, part_href=None):
-        self.children = []
-        self.name = name
-        self.part_href = part_href
-        self.sub_number = None
-
-    def add(self, name, part_href, level=0, is_part=True, index=None):
-        assert level == 0 or index is None
-        if level > 0 and self.children:
-            return self.children[-1].add(name, part_href, level - 1, is_part)
-        else:
-            t = TOC(name)
-            t.part_href = part_href
-            if index is not None:
-                self.children.insert(index, t)
-            else:
-                self.children.append(t)
-            if not is_part:
-                t.sub_number = len(self.children) + 1
-                return t.sub_number
-
-    def append(self, toc):
-        self.children.append(toc)
-
-    def extend(self, toc):
-        self.children.extend(toc.children)
-
-    def depth(self):
-        if self.children:
-            return max((c.depth() for c in self.children)) + 1
-        else:
-            return 0
-
-    def href(self):
-        src = self.part_href
-        if self.sub_number is not None:
-            src += '#sub%d' % self.sub_number
-        return src
-
-    def write_to_xml(self, nav_map, counter=1):
-        for child in self.children:
-            nav_point = nav_map.makeelement(NCXNS('navPoint'))
-            nav_point.set('id', 'NavPoint-%d' % counter)
-            nav_point.set('playOrder', str(counter))
-
-            nav_label = nav_map.makeelement(NCXNS('navLabel'))
-            text = nav_map.makeelement(NCXNS('text'))
-            if child.name is not None:
-                text.text = re.sub(r'\n', ' ', child.name)
-            else:
-                text.text = child.name
-            nav_label.append(text)
-            nav_point.append(nav_label)
-
-            content = nav_map.makeelement(NCXNS('content'))
-            content.set('src', child.href())
-            nav_point.append(content)
-            nav_map.append(nav_point)
-            counter = child.write_to_xml(nav_point, counter + 1)
-        return counter
-
-    def html_part(self, depth=0):
-        texts = []
-        for child in self.children:
-            texts.append(
-                "<div style='margin-left:%dem;'><a href='%s'>%s</a></div>" %
-                (depth, child.href(), child.name))
-            texts.append(child.html_part(depth + 1))
-        return "\n".join(texts)
-
-    def html(self):
-        with open(get_resource('epub/toc.html'), 'rb') as f:
-            t = f.read().decode('utf-8')
-        return t % self.html_part()
-
-