tools/examples: hardcode #!/usr/bin/python shebang
diff --git a/tools/tcpretrans.py b/tools/tcpretrans.py
index 442fd3e..47ac8c1 100755
--- a/tools/tcpretrans.py
+++ b/tools/tcpretrans.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/python
 # @lint-avoid-python-3-compatibility-imports
 #
 # tcpretrans    Trace or count TCP retransmits and TLPs.