How to retrieve all the attributes of LDAP database
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I am using **ldap module** of **python** to connect to **ldap server**. I am able to query the database but I dont know how to ***retrieve the fields present in the database***, so that I can notify the user in advance to quering the database, telling him that the field he is trying to access is not in the database. 

For example if the fields present are just 

    cn
    memberOf

and if the user tries to query the database with filter 

    cn and memberOf and notcontained

I should be able to know that the ***notcontained*** attribute is not in the dabase schema.

How can I accomplish this.

Thanks.