sync with rtgui-0.6

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diff --git a/components/rtgui/utils/perfect_hash/example-Python/PerfHash.py b/components/rtgui/utils/perfect_hash/example-Python/PerfHash.py
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+++ b/components/rtgui/utils/perfect_hash/example-Python/PerfHash.py
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+#!/usr/bin/env python
+"""
+This example shows how to use the class PerfHash.
+
+This class is designed for creating perfect hash tables at run time,
+which should be avoided, in particulat inserting new keys is
+prohibitively expensive since a new perfect hash table needs to be
+constructed.  However, this class can be usefull for testing.
+
+For practical programming purposes in Python the class PerfHash
+should never be used because Python's built-in dictionary is very
+efficient and always faster than PerfHash.
+"""
+
+import sys
+
+sys.path.append('..')
+from perfect_hash import PerfHash
+
+
+month = dict(zip('jan feb mar apr may jun jul aug sep oct mov dec'.split(),
+                 range(1, 13)))
+
+d = PerfHash(month)
+
+
+for m in month:
+    assert month[m] == d[m]
+
+d[True] = False
+
+assert d[True] == False
+
+for i in xrange(10):  # very expensive
+    d[i] = 2*i*i + 3*i -7
+
+assert d[4] == 37
+
+
+print 'OK'