code: def build_url(self, _name, **kwargs):
          '''
          String-based reverse API. Returns URL object::
  
              env.root.build_url('user.profile', user_id=1)
  
          Checks that all necessary arguments are provided and all
          provided arguments are used.
          '''
          used_args, subreverse =  self._build_url_silent(_name, **kwargs)
  
          if set(kwargs).difference(used_args):
              raise UrlBuildingError(
                  'Not all arguments are used during URL building: {}'\
                      .format(', '.join(set(kwargs).difference(used_args))))
          return subreverse.as_urf build_url(self, _name, **kwargs):
          '''
          String-based reverse API. Returns URL object::
  
              env.root.build_url('user.profile', user_id=1)
  
          Checks that all necessary arguments are provided and all
          provided arguments are used.
          '''
          used_args, subreverse =  self._build_url_silent(_name, **kwargs)
  
          if set(kwargs).difference(used_args):
              raise UrlBuildingError(
                  'Not all arguments are used during URL building: {}'\
                      .format(', '.join(set(kwargs).difference(used_args))))
          return subreverse.as_url
docs: String-based reverse API. Returns URL object::
  
              env.root.build_url('user.profile', user_id=1)
  
          Checks that all necessary arguments are provided and all
          provided arguments are used.