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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 register_function(self, function_name, function):
 """ Register a function for the module. The following functions can be registered .. py:function:: content_function() Called to discover what modules a container is displaying. This is used to determine when updates need passing on to the container and also when modules can be put to sleep. the function must return a set of module names that are being displayed. .. note:: This function should only be used by containers. .. py:function:: urgent_function(module_names) This function will be called when one of the contents of a container has changed from a non-urgent to an urgent state. It is used by the group module to switch to displaying the urgent module. ``module_names`` is a list of modules that have become urgent .. note:: This function should only be used by containers. """

        my_info = self._get_module_info(self._module.module_full_name)
        my_info[function_name] = function