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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 update_angular_template_hash(sender, **kwargs):
 """Listen for compress events. If the angular templates have been re-compressed, also clear them from the Django cache backend. This is important to allow deployers to change a template file, re-compress, and not accidentally serve the old Django cached version of that content to clients. """

    context = kwargs['context']  # context the compressor is working with
    compressed = context['compressed']  # the compressed content
    compressed_name = compressed['name']  # name of the compressed content
    if compressed_name == 'angular_template_cache_preloads':
        # The compressor has modified the angular template cache preloads
        # which are cached in the 'default' Django cache. Fetch that cache.
        cache = caches['default']

        # generate the same key as used in _scripts.html when caching the
        # preloads
        theme = context['THEME']  # current theme being compressed
        key = make_template_fragment_key(
            "angular",
            ['template_cache_preloads', theme]
        )

        # if template preloads have been cached, clear them
        if cache.get(key):
            cache.delete(key)