diff --git a/compressor/filters/base.py b/compressor/filters/base.py
index a49a529..284afcb 100644
--- a/compressor/filters/base.py
+++ b/compressor/filters/base.py
@@ -141,7 +141,7 @@ class CompilerFilter(FilterBase):
                 self.infile = open(self.filename)
                 options["infile"] = self.filename
 
-        if "{outfile}" in self.command and not "outfile" in options:
+        if "{outfile}" in self.command and "outfile" not in options:
             # create temporary output file if needed
             ext = self.type and ".%s" % self.type or ""
             self.outfile = NamedTemporaryFile(mode='r+', suffix=ext)
diff --git a/compressor/filters/cssmin/rcssmin.py b/compressor/filters/cssmin/rcssmin.py
index d3c6352..89aabe7 100644
--- a/compressor/filters/cssmin/rcssmin.py
+++ b/compressor/filters/cssmin/rcssmin.py
@@ -111,10 +111,10 @@ def _make_cssmin(python_only=False):
     escape = r'(?:\\(?:%(unicoded)s|%(escaped)s))' % locals()
 
     nmchar = r'[^\000-\054\056\057\072-\100\133-\136\140\173-\177]'
-    #nmstart = r'[^\000-\100\133-\136\140\173-\177]'
-    #ident = (r'(?:'
+    # nmstart = r'[^\000-\100\133-\136\140\173-\177]'
+    # ident = (r'(?:'
     #    r'-?(?:%(nmstart)s|%(escape)s)%(nmchar)s*(?:%(escape)s%(nmchar)s*)*'
-    #r')') % locals()
+    # r')') % locals()
 
     comment = r'(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/)'
 
@@ -192,7 +192,7 @@ def _make_cssmin(python_only=False):
         r'|(%(escape)s[^\\"\047u>@\r\n\f\040\t/;:{}]*)'
     ) % locals()).sub
 
-    #print main_sub.__self__.pattern
+    # print main_sub.__self__.pattern
 
     def main_subber(keep_bang_comments):
         """ Make main subber """
diff --git a/compressor/filters/jsmin/rjsmin.py b/compressor/filters/jsmin/rjsmin.py
index a3a1632..ff7dc0b 100755
--- a/compressor/filters/jsmin/rjsmin.py
+++ b/compressor/filters/jsmin/rjsmin.py
@@ -134,10 +134,10 @@ def _make_jsmin(python_only=False):
             if last is not None:
                 result.append((first, last))
             return ''.join(['%s%s%s' % (
-                chr(first),
-                last > first + 1 and '-' or '',
-                last != first and chr(last) or ''
-            ) for first, last in result])
+                chr(first2),
+                last2 > first2 + 1 and '-' or '',
+                last2 != first2 and chr(last2) or ''
+            ) for first2, last2 in result])
 
         return _re.sub(r'([\000-\040\047])', # for better portability
             lambda m: '\\%03o' % ord(m.group(1)), (sequentize(result)
diff --git a/compressor/templatetags/compress.py b/compressor/templatetags/compress.py
index 6e86d01..a45f454 100644
--- a/compressor/templatetags/compress.py
+++ b/compressor/templatetags/compress.py
@@ -201,7 +201,7 @@ def compress(parser, token):
 
     if len(args) >= 3:
         mode = args[2]
-        if not mode in OUTPUT_MODES:
+        if mode not in OUTPUT_MODES:
             raise template.TemplateSyntaxError(
                 "%r's second argument must be '%s' or '%s'." %
                 (args[0], OUTPUT_FILE, OUTPUT_INLINE))