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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 select_template_name(template_name_list, using=None):
 """ Given a list of template names, find the first one that exists. """

    if not isinstance(template_name_list, tuple):
        template_name_list = tuple(template_name_list)

    try:
        return _cached_name_lookups[template_name_list]
    except KeyError:
        # Find which template of the template_names is selected by the Django loader.
        for template_name in template_name_list:
            try:
                get_template(template_name, using=using)
            except TemplateDoesNotExist:
                continue
            else:
                template_name = six.text_type(template_name)  # consistent value for lazy() function.
                _cached_name_lookups[template_name_list] = template_name
                return template_name

        return None