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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 flatten_template_loaders(templates):
 """ Given a collection of template loaders, unwrap them into one flat iterable. :param templates: template loaders to unwrap :return: template loaders as an iterable of strings. :rtype: generator expression """

    for loader in templates:
        if not isinstance(loader, string_types):
            for subloader in flatten_template_loaders(loader):
                yield subloader
        else:
            yield loader