Javascript HashTable использовать ключ объекта

или urllib.unquote_plus

>>> import urllib
>>> urllib.unquote('erythrocyte+membrane+protein+1%2C+PfEMP1+%28VAR%29')
'erythrocyte+membrane+protein+1,+PfEMP1+(VAR)'
>>> urllib.unquote_plus('erythrocyte+membrane+protein+1%2C+PfEMP1+%28VAR%29')
'erythrocyte membrane protein 1, PfEMP1 (VAR)'