diff --git a/src/bin/image-minimizer b/src/bin/image-minimizer
index 297d4e52..27c3b52a 100755
--- a/src/bin/image-minimizer
+++ b/src/bin/image-minimizer
@@ -32,8 +32,8 @@ class ImageMinimizer:
     drops_rpm = set()
     ts = None
 
-    def __init__(self, filename, root, dryrun, verbose):
-        self.filename = filename
+    def __init__(self, _filename, root, dryrun, verbose):
+        self.filename = _filename
         self.prefix = root
         self.dryrun = dryrun
         self.verbose = verbose
@@ -173,12 +173,12 @@ def parse_options():
     parser.add_option("-v", "--verbose", action="store_true", dest="verbose",
         help="Display every action as it is performed.")
 
-    (options, args) = parser.parse_args()
+    (_options, _args) = parser.parse_args()
     if len(args) == 0:
         parser.print_help()
         sys.exit(1)
 
-    return (options, args)
+    return (_options, _args)
 
 
 if __name__ == "__main__":
diff --git a/src/pylorax/creator.py b/src/pylorax/creator.py
index 5b2b3f40..d46294fe 100644
--- a/src/pylorax/creator.py
+++ b/src/pylorax/creator.py
@@ -51,8 +51,8 @@ def is_image_mounted(disk_img):
     Return True if the disk_img is mounted
     """
     with open("/proc/mounts") as mounts:
-        for mount in mounts:
-            fields = mount.split()
+        for _mount in mounts:
+            fields = _mount.split()
             if len(fields) > 2 and fields[1] == disk_img:
                 return True
     return False
diff --git a/src/pylorax/imgutils.py b/src/pylorax/imgutils.py
index 12f17ce2..fc38d5f3 100644
--- a/src/pylorax/imgutils.py
+++ b/src/pylorax/imgutils.py
@@ -233,24 +233,24 @@ def mount(dev, opts="", mnt=None):
     if mnt is None:
         mnt = tempfile.mkdtemp(prefix="lorax.imgutils.")
         logger.debug("make tmp mountdir %s", mnt)
-    mount = ["mount"]
+    cmd = ["mount"]
     if opts:
-        mount += ["-o", opts]
-    mount += [dev, mnt]
-    runcmd(mount)
+        cmd += ["-o", opts]
+    cmd += [dev, mnt]
+    runcmd(cmd)
     return mnt
 
 def umount(mnt,  lazy=False, maxretry=3, retrysleep=1.0):
     '''Unmount the given mountpoint. If lazy is True, do a lazy umount (-l).
     If the mount was a temporary dir created by mount, it will be deleted.
     raises CalledProcessError if umount fails.'''
-    umount = ["umount"]
-    if lazy: umount += ["-l"]
-    umount += [mnt]
+    cmd = ["umount"]
+    if lazy: cmd += ["-l"]
+    cmd += [mnt]
     count = 0
     while maxretry > 0:
         try:
-            rv = runcmd(umount)
+            rv = runcmd(cmd)
         except CalledProcessError:
             count += 1
             if count == maxretry:
@@ -335,7 +335,7 @@ class LoopDev(object):
     def __enter__(self):
         self.loopdev = loop_attach(self.filename)
         return self.loopdev
-    def __exit__(self, exc_type, exc_value, traceback):
+    def __exit__(self, exc_type, exc_value, exc_tb):
         loop_detach(self.loopdev)
 
 class DMDev(object):
@@ -345,7 +345,7 @@ class DMDev(object):
     def __enter__(self):
         self.mapperdev = dm_attach(self.dev, self.size, self.name)
         return self.mapperdev
-    def __exit__(self, exc_type, exc_value, traceback):
+    def __exit__(self, exc_type, exc_value, exc_tb):
         dm_detach(self.mapperdev)
 
 class Mount(object):
@@ -354,7 +354,7 @@ class Mount(object):
     def __enter__(self):
         self.mnt = mount(self.dev, self.opts, self.mnt)
         return self.mnt
-    def __exit__(self, exc_type, exc_value, traceback):
+    def __exit__(self, exc_type, exc_value, exc_tb):
         umount(self.mnt)
 
 class PartitionMount(object):
@@ -412,7 +412,7 @@ class PartitionMount(object):
             os.rmdir(mount_dir)
         return self
 
-    def __exit__(self, exc_type, exc_value, traceback):
+    def __exit__(self, exc_type, exc_value, exc_tb):
         if self.mount_dir:
             umount( self.mount_dir )
             os.rmdir(self.mount_dir)
diff --git a/src/pylorax/ltmpl.py b/src/pylorax/ltmpl.py
index f3b3617e..af15bbc3 100644
--- a/src/pylorax/ltmpl.py
+++ b/src/pylorax/ltmpl.py
@@ -147,11 +147,11 @@ class LoraxTemplateRunner(object):
 
     * Commands should raise exceptions for errors - don't use sys.exit()
     '''
-    def __init__(self, inroot, outroot, yum=None, fatalerrors=True,
+    def __init__(self, inroot, outroot, yum_obj=None, fatalerrors=True,
                                         templatedir=None, defaults={}):
         self.inroot = inroot
         self.outroot = outroot
-        self.yum = yum
+        self.yum = yum_obj
         self.fatalerrors = fatalerrors
         self.templatedir = templatedir or "/usr/share/lorax"
         self.templatefile = None
@@ -455,9 +455,9 @@ class LoraxTemplateRunner(object):
             cmd = cmd[1:]
 
         try:
-            output = runcmd_output(cmd, cwd=cwd)
-            if output:
-                logger.debug('command output:\n%s', output)
+            _output = runcmd_output(cmd, cwd=cwd)
+            if _output:
+                logger.debug('command output:\n%s', _output)
             logger.debug("command finished successfully")
         except CalledProcessError as e:
             if e.output:
@@ -555,15 +555,15 @@ class LoraxTemplateRunner(object):
                 logger.debug("removefrom %s %s: no files matched!", pkg, g)
         # are we removing the matches, or keeping only the matches?
         if keepmatches:
-            remove = filelist.difference(matches)
+            files_to_remove = filelist.difference(matches)
         else:
-            remove = matches
+            files_to_remove = matches
         # remove the files
-        if remove:
+        if files_to_remove:
             logger.debug("%s: removed %i/%i files, %ikb/%ikb", cmd,
-                             len(remove), len(filelist),
-                             self._getsize(*remove)/1024, self._getsize(*filelist)/1024)
-            self.remove(*remove)
+                             len(files_to_remove), len(filelist),
+                             self._getsize(*files_to_remove)/1024, self._getsize(*filelist)/1024)
+            self.remove(*files_to_remove)
         else:
             logger.debug("removefrom %s: no files to remove!", cmd)
 
diff --git a/src/pylorax/sysutils.py b/src/pylorax/sysutils.py
index 601f9ba6..6f3f86ca 100644
--- a/src/pylorax/sysutils.py
+++ b/src/pylorax/sysutils.py
@@ -47,12 +47,12 @@ def touch(fname):
         pass
 
 
-def replace(fname, find, replace):
+def replace(fname, find, substitute):
     fin = fileinput.input(fname, inplace=1)
     pattern = re.compile(find)
 
     for line in fin:
-        line = pattern.sub(replace, line)
+        line = pattern.sub(substitute, line)
         sys.stdout.write(line)
 
     fin.close()
diff --git a/src/pylorax/treebuilder.py b/src/pylorax/treebuilder.py
index 633fb986..d34fcf1e 100644
--- a/src/pylorax/treebuilder.py
+++ b/src/pylorax/treebuilder.py
@@ -79,7 +79,7 @@ class RuntimeBuilder(object):
                                basearch=arch.basearch, libdir=arch.libdir)
         self.yum = yum
         self._runner = LoraxTemplateRunner(inroot=root, outroot=root,
-                                           _yum=yum, templatedir=templatedir)
+                                           yum_obj=yum, templatedir=templatedir)
         self.add_templates = add_templates or []
         self.add_template_vars = add_template_vars or {}
         self._installpkgs = installpkgs or []
diff --git a/src/sbin/livemedia-creator b/src/sbin/livemedia-creator
index 7e49d64a..fb23d33f 100755
--- a/src/sbin/livemedia-creator
+++ b/src/sbin/livemedia-creator
@@ -239,7 +239,7 @@ def default_image_name(compression, basename):
     return basename + SUFFIXES.get(compression, ".xz")
 
 
-if __name__ == '__main__':
+def main():
     # parse the arguments
     parser = lorax_parser()
     opts = parser.parse_args()
@@ -390,8 +390,8 @@ if __name__ == '__main__':
                               "multiple partitions. swap is allowed but not used.")
 
         if errors:
-            for e in errors:
-                log.error(e)
+            for _e in errors:
+                log.error(_e)
             sys.exit(1)
 
         # Make the image. Output of this is either a partitioned disk image or a fsimage
@@ -480,3 +480,6 @@ if __name__ == '__main__':
     log.info("Results are in %s", opts.result_dir or result_dir)
 
     sys.exit( 0 )
+
+if __name__ == '__main__':
+    main()
diff --git a/src/sbin/mkefiboot b/src/sbin/mkefiboot
index 38d85e5a..6b3793d6 100755
--- a/src/sbin/mkefiboot
+++ b/src/sbin/mkefiboot
@@ -113,7 +113,7 @@ def mkefidisk(efiboot, outfile):
                     outfile.write(infile.read())
             dm_detach(dmdev+"p1")
 
-if __name__ == '__main__':
+def main():
     parser = argparse.ArgumentParser(description="Make an EFI boot image from the given directory.")
     parser.add_argument("--debug", action="store_const", const=logging.DEBUG,
         dest="loglevel", default=log.getEffectiveLevel(),
@@ -157,3 +157,6 @@ if __name__ == '__main__':
         efiboot = tempfile.NamedTemporaryFile(prefix="mkefiboot.").name
         shutil.move(opt.outfile, efiboot)
         mkefidisk(efiboot, opt.outfile)
+
+if __name__ == '__main__':
+    main()
diff --git a/utils/test-parse-template b/utils/test-parse-template
index a94c2779..970f37ee 100755
--- a/utils/test-parse-template
+++ b/utils/test-parse-template
@@ -43,7 +43,7 @@ def readtemplate(templatefile):
     lookup = TemplateLookup(directories=parser.directories)
     return lookup.get_template(templatefile)
 
-if __name__ == '__main__':
+def main():
     # check args
     if len(sys.argv) == 1:
         print "usage: %s TEMPLATE [arg1=value1] [arg2=value2] ..."
@@ -78,3 +78,6 @@ if __name__ == '__main__':
     except Exception:
         print text_error_template().render()
         raise SystemExit(1)
+
+if __name__ == '__main__':
+    main()