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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(self, recipe=None, plugin=None):
 """ Get one or more recipes. :param recipe: Name of the recipe :type recipe: str :param plugin: Plugin object, under which the recipe was registered :type plugin: GwBasePattern """

        if plugin is not None:
            if recipe is None:
                recipes_list = {}
                for key in self.recipes.keys():
                    if self.recipes[key].plugin == plugin:
                        recipes_list[key] = self.recipes[key]
                return recipes_list
            else:
                if recipe in self.recipes.keys():
                    if self.recipes[recipe].plugin == plugin:
                        return self.recipes[recipe]
                    else:
                        return None
                else:
                    return None
        else:
            if recipe is None:
                return self.recipes
            else:
                if recipe in self.recipes.keys():
                    return self.recipes[recipe]
                else:
                    return None