Setup sys.path properly this time (I'll update the hacking guide to
explain what's been done)
diff --git a/examples/dwarf_die_tree.py b/examples/dwarf_die_tree.py
index 7eb07ff..66280e6 100644
--- a/examples/dwarf_die_tree.py
+++ b/examples/dwarf_die_tree.py
@@ -15,7 +15,7 @@
 try:
     import elftools
 except ImportError:
-    sys.path.extend(['.', '..'])
+    sys.path[0:0] = ['.', '..']
 
 from elftools.common.py3compat import bytes2str
 from elftools.elf.elffile import ELFFile