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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_from_string(arg):
 """ Select a template from a string, which can include multiple template paths separated by commas. """

    if ',' in arg:
        tpl = loader.select_template(
            [tn.strip() for tn in arg.split(',')])
    else:
        tpl = loader.get_template(arg)
    return tpl