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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 angular_templates(context):
 """Generate a dictionary of template contents for all static HTML templates. If the template has been overridden by a theme, load the override contents instead of the original HTML file. One use for this is to pre-populate the angular template cache. Args: context: the context of the current Django template Returns: an object containing angular_templates: dictionary of angular template contents - key is the template's static path, - value is a string of HTML template contents """

    template_paths = context['HORIZON_CONFIG']['external_templates']
    all_theme_static_files = context['HORIZON_CONFIG']['theme_static_files']
    this_theme_static_files = all_theme_static_files[context['THEME']]
    template_overrides = this_theme_static_files['template_overrides']
    angular_templates = {}

    for relative_path in template_paths:

        template_static_path = context['STATIC_URL'] + relative_path

        # If the current theme overrides this template, use the theme
        # content instead of the original file content
        if relative_path in template_overrides:
            relative_path = template_overrides[relative_path]

        result = []
        for finder in finders.get_finders():
            result.extend(finder.find(relative_path, True))
        path = result[-1]
        try:
            if six.PY3:
                with open(path, encoding='utf-8') as template_file:
                    angular_templates[template_static_path] = template_file.\
                        read()
            else:
                with open(path) as template_file:
                    angular_templates[template_static_path] = template_file.\
                        read()
        except (OSError, IOError):
            # Failed to read template, leave the template dictionary blank
            # If the caller is using this dictionary to pre-populate a cache
            # there will simply be no pre-loaded version for this template.
            pass

    templates = [(key, value) for key, value in angular_templates.items()]
    templates.sort(key=lambda item: item[0])

    return {
        'angular_templates': templates
    }