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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def print_examples(self, full=False):
 """ Print the examples and exit. :param bool full: if ``True``, print all examples; otherwise, print only selected ones """

        msg = []
        i = 1
        for key in sorted(self.DEMOS.keys()):
            example = self.DEMOS[key]
            if full or example["show"]:
                msg.append(u"Example %d (%s)" % (i, example[u"description"]))
                msg.append(u"  $ %s %s" % (self.invoke, key))
                msg.append(u"")
                i += 1
        self.print_generic(u"\n" + u"\n".join(msg) + u"\n")
        return self.HELP_EXIT_CODE