code: def by_id(cls, semantictag_id, autoflush=True):
  		'''Return the semantic tag with the given id, or None.
  
  		:param semantictag_id: the id of the semantic tag to return
  		:type semantictag_id: string
  
  		:returns: the semantic tag with the given id, or None if there is no tag with
  			that id
  		:rtype: ckan.model.semantictag.SemanticTag # TODO check this
  
  		'''
  		query = meta.Session.query(SemanticTag).filter(SemanticTag.id==semantictag_id)
  		query = query.autoflush(autoflush)
  		semantictag = query.first()
  		return semantictaf by_id(cls, semantictag_id, autoflush=True):
  		'''Return the semantic tag with the given id, or None.
  
  		:param semantictag_id: the id of the semantic tag to return
  		:type semantictag_id: string
  
  		:returns: the semantic tag with the given id, or None if there is no tag with
  			that id
  		:rtype: ckan.model.semantictag.SemanticTag # TODO check this
  
  		'''
  		query = meta.Session.query(SemanticTag).filter(SemanticTag.id==semantictag_id)
  		query = query.autoflush(autoflush)
  		semantictag = query.first()
  		return semantictag
docs: Return the semantic tag with the given id, or None.
  
  		:param semantictag_id: the id of the semantic tag to return
  		:type semantictag_id: string
  
  		:returns: the semantic tag with the given id, or None if there is no tag with
  			that id
  		:rtype: ckan.model.semantictag.SemanticTag # TODO check this