code: def __prepare_namespaces(self):
          
          # create needed namespaces
          self.namespaces = dict(
              text="urn:text",
              draw="urn:draw",
              table="urn:table",
              office="urn:office",
              xlink="urn:xlink",
              svg="urn:svg",
              manifest="urn:manifest",
          )
  
          # copy namespaces from original docs
          for tree_root in self.tree_roots:
              self.namespaces.update(tree_root.nsmap)
  
          # remove any "root" namespace as lxml.xpath do not support them
          self.namespaces.pop(None, None)
  
          # declare the genshi namespace
          self.namespaces['py'] = GENSHI_URI
          # declare our own namespace
          self.namespaces['py3o'] = PY3O_URI
docs: create proper namespaces for our document