ValueError: item is not in list

Question

I am making this simple code:

MyList=[]
valueA=1
valueB=2
valueC=3
MyList.append (valueA)
MyList.append (valueB)
MyList.append (valueC)
print (MyList)
print ([My         


        

Answer 1

Your mistake was that you put my_list into another anonymous list at the last line.It should be like this:

MyList=[]
valueA=1
valueB=2
valueC=3
MyList.append (valueA)
MyList.append (valueB)
MyList.append (valueC)
print (MyList)
print (MyList.index(valueB))

Output:

[1, 2, 3]
1

Answer 2

[MyList] is a list consisting of a single item, which is MyList.

I don't know why you have wrapped MyList in another list. You need to call index on MyList itself:

print(MyList.index(valueB))

And the result will be 1, not 0, because valueB is the second item in MyList.