[Fixed]-Django custom tags reusablity

Here’s a simple way to memoize your tag:

get_languages_cache = None

@register.simple_tag
def get_languages(obj):
    if get_languages_cache is None:
        get_languages_cache = obj.get_languages()
    return get_languages_cache

This assumes obj.get_languages() never returns None. Check this question for further discussion and examples of memoization in Python.