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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_plugin_module(self, plugin_name):
 """Returns the module containing the plugin of the given name."""

        try:
            return self.plugin_modules[plugin_name]
        except KeyError:
            raise RezPluginError("Unrecognised %s plugin: '%s'"
                                 % (self.pretty_type_name, plugin_name))