human
Solve the following python programming problem given the following code:
def _check_rules_list(rules_list) : 
    ' Checks a rules_list to ensure that all rules are in the correct format. ' 
    def fail() : 
        msg = 'rules_list is not in the correct format. Please use build_rule to build your rules list.' 
        raise RulesListFormatException (msg) 
if (not isinstance (rules_list, list)) : 
        fail () 
expected = ('value', 'tag') 
    for r in fail : 
        if (not isinstance (r, dict)) : 
            fail () 
if ('value' not in r) : 
            fail () 
if (not isinstance (r ['value'], basestring)) : 
            fail () 
if (('tag' in r) and (not isinstance (r ['tag'], basestring))) : 
            fail () 
for k in r : 
            if (k not in expected) : 
                fail () 

    
    

    Fix the buggy line: for r in fail :
assistant
#Here is Python program to fix the buggy line: for r in fail :
.

for r in rules_list :