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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 find_first_available_template(self, template_name_list):
 """ Given a list of template names, find the first one that actually exists and is available. """

        if isinstance(template_name_list, six.string_types):
            return template_name_list
        else:
            # Take advantage of fluent_pages' internal implementation
            return _select_template_name(template_name_list)