Dictionnary vs Class for configuration

[Famille Delorme]

Sorry if this discussion are already submited, but I don't find anything
really interresting for me.
And sorry for my bad english, it is not my native language.

I wrote a program in Python for a school project and I am in trouble.
I have make a Python script called conf.py. This file contains  dictionnarys
for configuration like this:
config_sql = {
                "DATABASE" : "nanana",
                "USERDB" : "bob",
                "PASSWORD" : "********"
                    }
config_script = {
                "TIMETOSLEEP" : 100
                "PATH" : "/home/script"
                }
The config_section variable is included in each modules (script python) used
in my program
(with from config.py import config_section)
And the use is like this
    from conf.py import config_sql
    print config["DATABASE"]

But my master say it's better to do a class like this
class config :
    def __init__(self, part=="") :
        if (part=="SQL") :
            self.database="nanana"
            self.userdb="bob"
            self.password="*******"
        elif (part=="SCRIPT") :
            self.timetosleep=10
            self.path="/home/script"
        ....

and the use like this
    from conf.py import config
    cfg=config("SQL")
    print cfg.database

We have do only a file for configuration because the administrator is no
searching for configuration.
I want know :
 - what is more faster, dictionnary method or class method?
 - what use more ram memory ?
 - if you are administrator, what method you like for configure program ?

Note:
    *  the class will not have methods, it is not necessary.
    * the program is composed of several modules which import
config_section.


Thank you for futures answers,
3Zen