human
Solve the following python programming problem given the following code:
def contact() : 
    ' Allow the user to add, update and delete their contacts ' 
    table = s3db.pr.contact 
    ptable = s3db.pr_person 
    if (auth.is_logged_in () or auth.basic ()) : 
        s3.filter = (table.pe_id == auth.user.pe_id) 
else : 
        redirect (URL (c = 'default', f = 'user', args = 'login', vars = { 
            '_next' : URL (c = 'msg', f = 'contact'), 
})) 
table.name.writable = table.name.readable = False 
    table.pe_id.writable = table.pe_id.readable = False 
    table.person_name.writable = table.person_name.readable = False 
    table.id.writable = False 
    def msg_contact_onvalidation(form) : 
        if auth.user : 
            form.vars.pe_id = auth.user.pe_id 
s3db.configure (table._tablename, onvalidation = prep) 
    def prep(r) : 
        if r.id : 
            pe_id = r.record.pe_id 
            if (auth.user and (auth.user.pe_id == pe_id)) : 
                return True 
else : 
                session.error = T ('Access denied') 
                return dict (bypass = True, output = redirect (URL (r = request))) 
else : 
            return True 
s3.prep = prep 
    response.menu_options = [] 
    return s3_rest_controller ('pr', resourcename) 

    
    

    Fix the buggy line: s3db.configure (table._tablename, onvalidation = prep)
assistant
#Here is Python code to fix the buggy line: s3db.

s3db.configure (table._tablename, onvalidation = def msg_contact_onvalidation()