diff --git a/shell/ext-py/sqlparse-0.1.7/sqlparse/engine/__init__.py b/shell/ext-py/sqlparse-0.1.7/sqlparse/engine/__init__.py
index 62c82b8ad..d262f7452 100644
--- a/shell/ext-py/sqlparse-0.1.7/sqlparse/engine/__init__.py
+++ b/shell/ext-py/sqlparse-0.1.7/sqlparse/engine/__init__.py
@@ -48,16 +48,25 @@ class FilterStack(object):
             splitter = StatementFilter()
             stream = splitter.process(self, stream)
 
-        if self._grouping:
+        # import StripCommentsFilter in the run() method to avoid a circular dependency.
+        # For stripping comments, the only grouping method we want to invoke is
+        # grouping.group(), this considerably improves performance.
+        strip_comments_only = False
+        if self.stmtprocess and len(self.stmtprocess) == 1:
+          from sqlparse.filters import StripCommentsFilter
+          strip_comments_only = isinstance(self.stmtprocess[0], StripCommentsFilter)
 
+        if self._grouping:
             def _group(stream):
                 for stmt in stream:
-                    grouping.group(stmt)
+                    if strip_comments_only:
+                        grouping.group_comments(stmt)
+                    else:
+                        grouping.group(stmt)
                     yield stmt
             stream = _group(stream)
 
         if self.stmtprocess:
-
             def _run1(stream):
                 ret = []
                 for stmt in stream: