strip spaces from the name of classes in affinity.csv or classes.csv

I created a new dataset and started getting a lot of errors, number of data being zero, etc. Turns out I formed the classes.csv and affinity.csv as follows:

classes.csv
item1, item2

affinity.csv
item1, item2
1, -1
-1,1

because both have a space behind `item2` it doesn't through the error but it also doesn't recognise the name in the list of data