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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(self, name):
 """ Returns a plugin by name and raises ``gemstone.errors.PluginDoesNotExistError`` error if no plugin with such name exists. :param name: a string specifying a plugin name. :return: the corresponding plugin instance. """

        for plugin in self.plugins:
            if plugin.name == name:
                return plugin

        raise PluginDoesNotExistError("Plugin '{}' not found".format(name))