diff --git a/Parser/pgen/pgen.py b/Parser/pgen/pgen.py
index cd473b30d8..bf3472d717 100644
--- a/Parser/pgen/pgen.py
+++ b/Parser/pgen/pgen.py
@@ -10,15 +10,11 @@ import importlib.machinery
 CURRENT_FOLDER_LOCATION = os.path.dirname(os.path.realpath(__file__))
 LIB_LOCATION = os.path.realpath(os.path.join(CURRENT_FOLDER_LOCATION, '..', '..', 'Lib'))
 TOKEN_LOCATION = os.path.join(LIB_LOCATION, 'token.py')
-TOKENIZE_LOCATION = os.path.join(LIB_LOCATION, 'tokenize.py')
 
 token = importlib.machinery.SourceFileLoader('token',
                                              TOKEN_LOCATION).load_module()
-# Add token to the module cache so tokenize.py uses that excact one instead of
-# the one in the stdlib of the interpreter executing this file.
-sys.modules['token'] = token
-tokenize = importlib.machinery.SourceFileLoader('tokenize',
-                                                TOKENIZE_LOCATION).load_module()
+
+import tokenize  # from stdlib
 
 from . import grammar
 
@@ -184,16 +180,16 @@ class ParserGenerator(object):
         dfas = collections.OrderedDict()
         startsymbol = None
         # MSTART: (NEWLINE | RULE)* ENDMARKER
-        while self.type != self.tokens.ENDMARKER:
-            while self.type == self.tokens.NEWLINE:
+        while self.type != tokenize.ENDMARKER:
+            while self.type == tokenize.NEWLINE:
                 self.gettoken()
             # RULE: NAME ':' RHS NEWLINE
-            name = self.expect(self.tokens.NAME)
+            name = self.expect(tokenize.NAME)
             if self.verbose:
                 print("Processing rule {dfa_name}".format(dfa_name=name))
-            self.expect(self.tokens.OP, ":")
+            self.expect(tokenize.OP, ":")
             a, z = self.parse_rhs()
-            self.expect(self.tokens.NEWLINE)
+            self.expect(tokenize.NEWLINE)
             if self.verbose:
                 self.dump_nfa(name, a, z)
             dfa = self.make_dfa(a, z)
@@ -309,7 +305,7 @@ class ParserGenerator(object):
         # ALT: ITEM+
         a, b = self.parse_item()
         while (self.value in ("(", "[") or
-               self.type in (self.tokens.NAME, self.tokens.STRING)):
+               self.type in (tokenize.NAME, tokenize.STRING)):
             c, d = self.parse_item()
             b.addarc(c)
             b = d
@@ -320,7 +316,7 @@ class ParserGenerator(object):
         if self.value == "[":
             self.gettoken()
             a, z = self.parse_rhs()
-            self.expect(self.tokens.OP, "]")
+            self.expect(tokenize.OP, "]")
             a.addarc(z)
             return a, z
         else:
@@ -340,9 +336,9 @@ class ParserGenerator(object):
         if self.value == "(":
             self.gettoken()
             a, z = self.parse_rhs()
-            self.expect(self.tokens.OP, ")")
+            self.expect(tokenize.OP, ")")
             return a, z
-        elif self.type in (self.tokens.NAME, self.tokens.STRING):
+        elif self.type in (tokenize.NAME, tokenize.STRING):
             a = NFAState()
             z = NFAState()
             a.addarc(z, self.value)
@@ -365,7 +361,7 @@ class ParserGenerator(object):
         while tup[0] in (tokenize.COMMENT, tokenize.NL):
             tup = next(self.generator)
         self.type, self.value, self.begin, self.end, self.line = tup
-        #print self.tokens['tok_name'][self.type], repr(self.value)
+        # print(getattr(tokenize, 'tok_name')[self.type], repr(self.value))
 
     def raise_error(self, msg, *args):
         if args: