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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 new_name(self, template=u"xxx_todo_changeme"):
 """Return a string suitable for use as an identifier The new name is guaranteed not to conflict with other identifiers. """

        name = template
        while name in self.used_names:
            name = template + unicode(self.numbers.next())
        self.used_names.add(name)
        return name