diff --git a/bin/spack b/bin/spack
index 9b1276a866639e385b7378b4b08ddae8e5c9ece4..e9307d1485ac0284521b7d5513d727143ce0b009 100755
--- a/bin/spack
+++ b/bin/spack
@@ -77,7 +77,7 @@ import llnl.util.tty as tty
 from llnl.util.tty.color import *
 import spack
 from spack.error import SpackError
-from external import argparse
+import argparse
 
 # Command parsing
 parser = argparse.ArgumentParser(
diff --git a/lib/spack/spack/test/versions.py b/lib/spack/spack/test/versions.py
index c051895ca3a466211b3be1c167c1859b8cccff8a..a3a328fb14e55c341e671e65d3f3e9d406032354 100644
--- a/lib/spack/spack/test/versions.py
+++ b/lib/spack/spack/test/versions.py
@@ -424,4 +424,4 @@ def test_get_item(self):
         self.assertEqual(repr(b), 'Version(\'1_2-3\')')
         self.assertEqual(str(b), '1_2-3')
         # Raise TypeError on tuples
-        self.assertRaises(TypeError, b.__getitem__, 1, 2)
\ No newline at end of file
+        self.assertRaises(TypeError, b.__getitem__, 1, 2)
diff --git a/lib/spack/spack/version.py b/lib/spack/spack/version.py
index 7e5878383d064810fde5081fd730a6bae2ceebde..683964394175e87b1a2a946ba2d97500405f15d0 100644
--- a/lib/spack/spack/version.py
+++ b/lib/spack/spack/version.py
@@ -202,9 +202,9 @@ def __getitem__(self, idx):
             # Currently len(self.separators) == len(self.version) - 1
             extendend_separators = self.separators + ('',)
             string_arg = []
-            for token, separator in zip(self.version, extendend_separators)[idx]:
+            for token, sep in zip(self.version, extendend_separators)[idx]:
                 string_arg.append(str(token))
-                string_arg.append(str(separator))
+                string_arg.append(str(sep))
             string_arg.pop()  # We don't need the last separator
             string_arg = ''.join(string_arg)
             return cls(string_arg)