def insertRuleset(self, ruleset, domain):
		'''增加一个robots.txt规则集'''
		cur = self.conn.cursor()
		cur.execute("SELECT did FROM Domains WHERE domain=?", (domain,))
		did = cur.fetchone()[0]
		cur.execute("INSERT INTO Rulesets VALUES (NULL,?,?)",(did, ruleset))
		# 写入到文件
		self.conn.commit()
def _maybe_name(obj):
  """Returns object name if it has one, or a message otherwise.

  This is useful for names that apper in error messages.
  Args:
    obj: Object to get the name of.
  Returns:
    name, "None", or a "no name" message.
  """
  if obj is None:
    return "None"
  elif hasattr(obj, "name"):
    return obj.name
  else:
    return "<no name for %s>" % type(obj)