def lookup(content):
    value=True
    if any(x not in content for x in ['A','B','C']):
        value = False
    print (value)
What i want is check if any of these 'A' 'B' 'C' is in a string , for example if string equates ABCAA then the value will be true, if the string is ABDC then value is wrong because content contains a char not defined in my list above.The issue is i'm getting false with that function for 'ABC' which isn't supposed to happen.
 
     
    