Update PxCorpus.py

PxCorpus.py

@@ -49,7 +49,7 @@ class StringIndex:
                 continue
 
             # Index terms by their first letter and length
-            key = (str(term)[0], len(term))
+            key = (term[0], len(term))
 
             if key not in self.vocab_struct:
                 self.vocab_struct[key] = []
@@ -60,7 +60,7 @@ class StringIndex:
 
     def find(self, term):
         print(f"'{term}'")
-        return term in self.vocab_struct[(str(term)[0], len(str(term)))]
+        return term in self.vocab_struct[(term[0], len(str(term)))]
 
 _VOCAB = StringIndex(vocab=open("./vocabulary_nachos_lowercased.txt","r").read().split("\n"))