fixed flake errors

lib/spack/spack/architecture.py

@@ -76,7 +76,6 @@
 will be responsible for compiler detection.
 """
 import os
-import imp
 import inspect
 
 from llnl.util.lang import memoized, list_modules, key_ordering
@@ -206,15 +205,12 @@ def detect(self):
         """
         raise NotImplementedError()
 
-
     def __repr__(self):
         return self.__str__()
 
-
     def __str__(self):
         return self.name
 
-
     def _cmp_key(self):
         t_keys = ''.join(str(t._cmp_key()) for t in
                          sorted(self.targets.values()))
@@ -343,6 +339,7 @@ def to_dict(self):
         d['version'] = self.version
         return d
 
+
 @key_ordering
 class Arch(object):
     """Architecture is now a class to help with setting attributes.
@@ -383,11 +380,9 @@ def __str__(self):
         else:
             return ''
 
-
     def __contains__(self, string):
         return string in str(self)
 
-
     def _cmp_key(self):
         if isinstance(self.platform, Platform):
             platform = self.platform.name