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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 _get_role_description(self, role):
 """ Returns the description of role. :param role: The role. :type role: str :return: The description of role. :rtype: str """


        parameter = 'role-' + role.lower()
        if self.configure.has_parameter(parameter):
            return self.configure.get_parameter(parameter)
        return None